Marijuana Growing & Seed Germination

– GERMINATION (Marijuana Cannabis Seed Germination and More)

Green CulturED Cannabis College


Seeds can and should be stored in a refrigerator if they are not going to be used right away. The best storage method is to place seeds in a film canister with a few grains of rice (uncooked rice will absorb moisture). Place canister with contents in the refrigerator and they should have a shelf life of two years or more. The longer you wait to use your seeds, the greater the chances of germination rates lowering.  If you wish to store for longer periods of time, then you can freeze them but make sure they are well dried before doing so.



Use these steps as a guideline…
1) Add two tablespoons of bleach to one gallon of distilled water.
2) Soak seeds for 24 hours.
3) Every six hours check for cracked seeds if you find one take it out.
Place in your medium with the pointed end up.
4) After 24 hours place the remaining seeds in your medium.

There are many ways to germinate your seeds, this one is recommended by one of our growing experts.  It’s easy enough for the new grower so it is highly recommended. Before you start, place your seeds in the refrigerator overnight. This will help induce a better germination rate. If using very fresh seeds, make sure they are allowed to dry for at least two to three weeks before using.





Once cuttings are planted and watered, place them under a fluorescent lamp where they will stay until rooted. Softwood cuttings require bottom heat of about 21C (71 F), which is usually room temperature for most propagation areas. Keeping trays of cuttings on cold concrete floors will slow down root development. Avoid high temperatures in the tray as they force the cuttings to produce top growth instead of roots, using up food reserves in the cutting. High humidity levels help reduce water loss from the cutting leaves, but they can also encourage plant diseases to multiply and attack your young plants.

If you use a clear dome over your tray, remove it at least once a day for a few minutes to air out the tray, and wipe condensed moisture out of the cover, it simply interferes with light reaching the cuttings. While domes can reduce water loss from cuttings they can also trap heat. Keep the fluorescent lamps at least a foot (30 cm) above the top of the dome. A small thermometer placed in the propagation tray will help keep track of propagation temperatures.

Since cuttings cannot spend their whole lives under a dome, the sooner they can adapt to life in the open air, the better. Once cuttings have lived inside the dome for a week or so, by removing the clear cover for a few hours during the light period, watching carefully for wilting. If they do show signs of stress, replace the cover and try again a few days later. While some
crops take longer than others to root, plants that seem addicted to their covers may be suffering from fungus disease – treat with “No Damp” according to directions. The other possibility is high temperatures inside the dome. (above 24C=75F )


Budtender Certification


Newly planted cuttings are watered in well with a mix of water and power thrive (one tablespoon/ one gallon) to supply vitamins that reduce plant stress, and also to provide good contact between the cutting’s stem and the grow medium. If the cuttings are cared for under moderate conditions (21C tray temperature, fluorescent lighting ) they will likely not need watering for about 59 days. Plant rooting in fast-draining mediums such as perlite or hydro corn may need watering more frequently. Once cuttings can stand up well with the covers removed, they will need watering more often. Keeping cuttings too wet will cause root and stem rot; letting cuttings dry out will kill them just as quickly. Let experience and the appearance of the cuttings be your guide.

Giving new cuttings fertilizer can actually cause slow rooting – the plants have no good reason to grow roots! Once cuttings show signs of having new roots- either fine white roots showing on the bottom of the rock wool cube or new light green top growth start feeding cuttings with the mild fertilizer solution. Good baby food for newly- rooted cuttings is 1/3 strength flowering fertilizer. This food helps the new plants to grow deep, strong roots, without forcing top growth When cuttings are definitely rooted and producing new top growth, with the dome permanently removed, lower the fluorescent lamps gradually closer to tops of cuttings, watching closely for wilting or signs of stress. It’s possible to gradually drop the lamp within 8cm (3 inches) above the growing tips. If you are keeping these rooted cuttings under the fluorescent lamps, be sure to raise lamps as plants grow taller to avoid cooking new top growth Continue watering and feeding as required, using mild fertilizer until they are transplanted to
stronger light levels.



Keep Fluorescent lamps on for 18-24 hours a day while cuttings are rooting. Once rooted and being fed the mild fertilizer solution, they will need a six-hour night to grow best. Match the timing of the dark period of the cuttings to the night, they will have when transplanted into a grow-room or greenhouse.



Since cuffings are taken from healthy, disease and pest-free stock plants, and the grow mediums we use for rooting cuttings are considered disease-free at the start, we usually don’t have to use fungicides until a week or so after starting the cuttings – use “No Damp” fungicide solution as a foliar spray or water it into the medium. (1 Oml “No Damp” with one liter of water) Repeat once a week as a precaution while cuttings are rooting.

Insects can be very destructive to young plants. Spider mites and fungus gnats are two of the worst insects to discover in a propagation tray since they can destroy all the cuttings and set back the garden. “Bug Kill” works well against spider mites – be sure to spray underside of leaves regularly to kill adults and hatchling as they emerge from eggs. Spray inside of the tray to pick off strays crawling from plant to plant.

Fungus gnats lay eggs in the growing medium, and when the eggs hatch, their tiny larva chew new roots to suck food from the plants. They weaken plants and create disease problems too. They carry fungus spores on their bodies, which attack plants through their damaged roots. Use “sticky cards” to check for signs of Fungus gnats In the propagation tray, and treat all cuttings with Wilson’s “Potting Soil Insecticide Dust” or similar mild pesticide if signs of gnats appear.


Germination and More

Starting Media and Nutrients

Any propagation medium must be thoroughly soaked before seeds are sown to assure uniform distribution of moisture. There are many different propagation media available. Seeding trays can be filled with a soilless mix, such as peat and perlite. Peat pellets
are also popular starters. Seedlings grown in a soil-less mix may have enough nutrients available to them from the media that they would not need any additional nutrients for the first few weeks of growth, and therefore could be watered with fresh water only. However, seedlings in an inert medium, such as rock wool or oasis, will definitely require a nutrient solution at all times.
Rock wool blocks are available in several sizes and are designed so that seeds can be placed directly into seeding cubes, then, as the plants develop, the cubes can be nested inside larger blocks, for a “pot in a pot” system. This minimizes transplant shock since the larger block consists of the same material as the germination cube. Oasis horticubes are similar to rock wool cubes in that they are inert, sterile blocks with excellent drainage. Other cubes made of urethane foam and paper fiber are also available.
Tomato seeds should be sown 1/4 to 3/8 inch (0.6 to 1cm) deep. Sprinkle a thin layer of vermiculite over the seeds or cover the germination cubes or pots with a large piece of clear plastic to conserve moisture at the surface. Avoid the use of plastic if the cubes receive direct sunlight, as the temperature may get too hot for good germination. The plastic must be removed as soon as emergence begins.

Seedling system design Overhead watering is the most common method used for germinating seedlings. It is important for the seedlings to be in full sun and at the proper temperature as soon as germination occurs. When watering, the water must be
sprinkled uniformly over all seedlings to avoid uneven growth. The plants must be checked often to assure they do not become water-stressed. Flood and drain (ebb and flow) systems can also be very effective for germinating seedlings. Nutrient solution or water floods a shallow tray containing the sown cubes or pots, providing moisture from the bottom, which will diffuse throughout the propagation block by capillary action. Once the blocks are evenly moist, the tray is drained, which allows the cubes or pots to drain and assure aeration of the roots. This process will need to be repeated often throughout the day, but may not need to be
done at all during the night. The advantages of this system are even moisture, no physical beating of the leaves and tender plants, and low labor costs (especially if timers are used). In any event, the temperature of the irrigation solution should
be at least 18 C (64 F). Irrigating seedlings with colder water will result in slower growth. During winter months, especially in Northern latitudes, supplemental light may be required for the strong growth of seedlings. The lights should operate 14 to 18 hours per day.



The three stages of early development are germination, post-emergence, and transplant. Germination should occur within one week of seeding, post-emergence is generally 5 to 12 days, and transplanting should be done between 12 and 14 days from seeding. Once true leaves appear (during post-emergence), seedlings should be transferred into larger growing blocks (pots) from the original seedling cubes, then evenly spaced to maximize light to each plant, without any crowding or shading. The
transplants must be spaced so as not to touch one another and may need to be spread several times during their growth. If crowded, the plants will become spindly. A good transplant is one that is as wide as it is tall. If plants are somewhat “leggy”, with
long stems, they can be transferred into the larger blocks with their stems bent 180, so the original cube is upside-down inside the larger block, and the main stem forms a “U” shape, emerging vertically upward from the block. Tomato plants readily grow
adventitious roots from the stems if given the opportunity, producing a stronger plant with more roots. Adventitious roots will grow from the bent stem inside the block. Transplanting into the final growing media should be done before any flowering. The final growing media should be properly leached and moistened and be at the proper temperatures before plants are brought in. Plants should be irrigated with the nutrient solution immediately after moving.

The spacing of tomatoes in hydroponic systems can be much denser than in soil. As little as two square feet per plant (0.2 square meters per plant) have been used with good yields and quality under high light conditions. Spacing is a function of sunlight, so in areas of lower light wider spacing should be applied. pH is a wonderful early warning system of problems before they happen because it illustrates the condition of your reservoir water!

A pH reading should be made from your reservoir. There are many factors that contribute to a changing of the pH of your reservoir, but the most common will be due to your plants taking up nutrients and leaving “salts” behind. A pH reading must be taken daily and preferably before you add nutrient (to give you an idea of what your plants are doing to the reservoir water) and a few hours after nutrient is added to the reservoir.

Our serious tip on pH’s is getting the right pH tester. Most professional growers will stray away from any electronic pH tester, as they tend to be inaccurate and often require calibration (which relies on a calibrated pH solution). Our tip is to buy a cheap (<$5.00) liquid pH tester from a hydroponic shop that gives readings in the colors Yellow, Green and Blue (these never need calibrating and will give 100% accurate readings) Maintain nutrient pH between 5.6 and 6.2.

If your readings are low < 5.0, the reservoir water will be acidic. On the color meter, this will be a yellow shade. This might be a good sign showing your plants are feeding and depositing “salts” into the reservoir changing the pH reading to “Yellow” or acidic. Simply ad “pH up” available from a hydroponics shop, to bring the pH back to Green (5.6 – 6.2) two hours after adding your nutrient. If your reading is high >6.2, the reservoir water will be alkaline. On the color meter, this will be a blue shade. We often have found a reservoir going blue can be an early indicator of plant problems, especially when the meter goes blue on a continual basis. By adding “pH down” available from a hydroponics shop, you can bring the pH back to green (5.6 – 6.2) two hours after adding your nutrient. A non-consistent pH (i.e. a pH that goes up and down like a yo-yo) is often a sign of lack of water conditioner: See Tip 3 on Water Conditioner


Parts Per Million (or PPM Meter)

If you’re a serious grower you will understand the importance of a PPM Meter. People who don’t use a PPM Meter on a daily basis are looking for trouble. Our serious tip on PPM is: Never, never, ever ad nutrient “by eye” as you will never know how many “parts per million of nutrients” are in your reservoir to start with. A marijuana plant is a living plant that has needs that might change from day today. If the temperature happens to be a bit low it might not feed that day. And what does the amateur grower do? Blindly throw another cup or three of 2 part nutrients, plus a splash of Hydro Minerals? This would mean the reservoir would have double the required nutrient that day and is heading for a disaster.

Good PPM meters are often about $100. Professional growers will stay away from any PPM meter that requires calibration… believe me they are no good. The best PPM meter is one that is self-calibrating. Professional growers tend to maintain PPM’s at about 1600 – 1800. When adding nutrients they ad small amounts at a time so as not to exceed their PPM maximum and take PPM measurements over a period of time. Reservoir PPM’s that go down is generally a good sign, showing plants are feeding and using the nutrient on a daily basis. Reservoir PPM’s that are stable or go up are an early warning indicator that your plants are not feeding and the plants might be in stress for some reason or another. Read Water Conditioner and pH Tips section for help in this regard. PPM Meters stop a major problem of over-feeding your plants, one of the top 5 causes of plant deaths in the growers’ bible.


The Water Conditioner

A water conditioner is an often unknown element when growing hydroponically. If you have read any outdated books by Rosenthal or his other hippie mates that you should “dump” or “flush” your reservoir every two weeks, then sit down, take your blindfold off and read this: As you have read above, plants use nutrient and dump salt and residues in the reservoir. Plants will sometimes use more of one element and less of another, which will cause solidification of salts of one type or another in your reservoir.

Rosenthal and his hippie mates got around this problem by flushing regularly which cleaned all salt build-up in the reservoir, and replaced the nutrient to the correct PPM’s; only to repeat this procedure two weeks later! Many professional growers will not flush at all during the entire grow cycle and only flush two or three times in the flowering cycle!

They have perfectly balanced reservoirs and no salt residue buildup! What is their secret? Water Conditioner (a generalized name) also called “Bio-Acids” or “Plant Acids” or “Sea Acids” depending on the manufacturer. in Australia, they are called BIO-Earth Sea Acids and solve many growers reservoir imbalance problems. Bio-Acids as I like to call them to function to break down compounds found in soils and thereby release and chelate nutrients.

When such organic plant acids are added to inorganic nutrient solutions or to a fertilizer treated rock wool or soil, pH is naturally balanced, trace elements are naturally chelated and the organic acid levels are greatly improved. Research shows conclusively that organic acids are so vital a component of plant chemistry, that when excluded from the cultivation equation, yields are drastically reduced. Significant improvements are noticed when re-introduced and normal plant processes are restored. Talk to your local hydroponic shop about water conditioners and bio/plant acids which will reduce the amount of nutrients you waste every flush. If your hydro shop doesn’t sell this product, go somewhere else. Some hydro shops make their living on ignorant people who flush their nutrients down the drain on a regular basis.



Often an underestimated element of growing marijuana: Many amateurs strive to find the reasons why they only pull two ounces of bud a plant when a professional using the same strain will reap a pound per plant. Professionals tip of the day: Lights = Poundage (given all other factors are accounted for) Generally speaking, 1000watt HID, or 1000w MH lamps will provide the heaviest crops. The more light in the grow area, the heavier resin laden buds you will pull. This might cause some controversy out there, but this statement is the reality because it’s simple and it works: more light means more bud, from top to bottom! Most professionals will use a light moving system in larger areas to save on costs of running electricity thirsty ballast’s.

Professionals find that more light will lower the grow cycle times, and will reduce the flowering cycle time so that your risk is also reduced. “All other factors accounted for” are balanced pH, PPM’s, water conditioning, rare-mineral supplement, temperature, airflow, co2, and humidity. Persons concerned with large power consumption, consider this: A GEC electric heater or an air-conditioner can use 2500w constantly whilst in use. 2 x 1000w Metal Halide systems will use a little over 2200w total. Your growing time is reduced with more light so you can switch to the flowering cycle quicker. On a 12 hour on, 12 hours off grow cycle you are only using 1100w in a 24 hour period! More lights = greater heat.

Make sure you read the temperature, Free Co2, airflow & ventilation tips to keep a constant grow room temperature. I don’t get into discussions about which is better HID or MH. Professionals that I talk to find that the end results are pretty much the same for each lamp, and stress that people like Rosenthal and his hippie mates get their g-strings in a knot over color spectrums and the like when the most important factor is the number of lumens (or light) produced per square foot of growing space. Finally, another modern professional tip: To reduce noise from your HID or MH Ballast, sit them on a block of fire-resistant “grodan” grow-wool. This will simply cut a huge amount of Ballast noise emanating from your grow room. If you’re worried about the garden, you can slip a piece of concrete sheeting between the Ballast and the grodan to reduce heat…

– 1000w Ballast on top
– Fireproof and Fire-resistant concrete sheeting
– Fire-resistant grodan slab to cushion sound


Temperature, Free C02, Airflow, Humidity and Ventilation

Also another in the top 5 casualty list: Incorrect temperature, airflow, and ventilation.


Ventilation and Airflow
When using high-temperature globes in a confined space it is essential to have adequate airflow and ventilation. If these criteria are not met, your plants may burn or dry in the heat or event worse start a fire. Professional growers state that you can never have enough ventilation indoors! Install a ceiling exhaust fan in reverse to bring in air from outside, and install a second one normally to pump the air out of the room, so you know your grow room is getting “fresh” outdoors air and not stale indoor air.

If this doesn’t reduce heat enough, buy exhaust fans certified to pull 450m3+ per hour; they’re worth the money. Install cheap “central heating” piping if you have to pull air from an area away from the grow room. See “reducing fan noise” picture for soundproofing.

Use rotating floor fans to “stir up” and circulate air within the grow room.

It can be a difficult problem, especially in the flower cycle. Excess humidity can cause molds to rot your marijuana. Professional growers are of the opinion that excess humidity can reduce THC in your buds.

Try and reduce your humidity to 50- 60. This can be an extremely difficult task at times, especially when you have a room full of marijuana perspiring buckets of water out their leaves. We found a simple and effective solution to reducing humidity, however, we must warn that this will increase temperature. Its called free Co2.



– By drawing Co2 from Gas Stove
– Use Duct tubing to grow room
– More tubing will cool the Co2
– Use existing Kitchen Fan

With this method, you can significantly lower humidity, control temperature, and have abundant Co2 flowing over your plants from above for next to nothing. The temperature was controlled by turning down the flame or increased by lighting another burner. There is no danger of naked flames in the grow room as flames remain in the kitchen. The kitchen had an existing exhaust fan that was secured above to some central heating duct pipe that ran to the grow room. In hotter weather, the duct tubing was extended from 10ft to 40ft. By running the excess tubing up and down the roof, it reduced the temperature, however, there was still abundant cool Co2 flowing into the room.

The humidity rose a little after this extension. I don’t know if you can appreciate the sound of 4 Exhaust fans running at once, but one might compare it to a jackhammer from inside a grow room!

Here are some more excellent tips on reducing fan noise:

– Cut hole in the ceiling and fit ducting
– Attach exhaust fan to duct tube
– Attach 4 nylon lines to fan
– Join to roof above with the single line
– Enjoy the peace and quiet!



Many of the temperature-related topics were discussed in airflow above, but this is a pointer that needs mentioning: Controversial like always, we decided that what we read in Rosenthals and other books was a load of shit regarding temperature. Growers found cultivating marijuana strains at suggested temperatures of 25c -27c achieved hemp quality ganja which was a shit smoke.

The same strains grew at 35c – 37c was rocket fuel and physically blew your socks off. Maybe it was a particular strain, but we will advise you as time goes on as professional growers give me information on this topic. Here are some tips on tailoring the fertilizer mix to the particular stage of a plant’s development…

Stage Cutting Early Vegetative Rapid Vegetative

Days 7-21 6-10 0-14

Fertilizer Phosphorus Grow/Bloom Grow Formula
Superthrive, Mixture high nitrogen low
H202, Moderate levels phosphorous
WillardsWater of nitrogen and phosphorous

Lighting 7500K Flour 5600K Halide Iwasaki 3700K Halide Eye Lighting Iwasaki

Stage Early Bloom Late Bloom Finish/Fruiting

Days +/- 14 +/- 32 +/- 10

Fertilizer Grow/Bloom Mixture Bloom Formula Mixture Organic Mix
Low Dosage Low Nitrogen

Lighting 2100K Retro HPS 2100K Retro HPS (Iwasaki) 2100K Retro HPS (Iwasaki)



Energy Supply

Every living creature needs the energy to live, develop, and grow. For most living creatures the most important energy source is sugar (glucose). Green plants are the only ones capable of producing these sugars themselves. These sugars are produced from water, which is being absorbed through the roots and carbon dioxide, which is being absorbed from the air. In order to make sugar out of these matters, the plant needs light. This process takes place in the green pigment, (chloroplasts) and is called; photosynthesis. (photo=light, synthesis=produce, therefore photosynthesis means; produce through light).


As above, the plant needs light for its energy supply. Because we are talking about growing indoors, we will have to supply a light source. Normal lamps are less suitable for the job. A plant needs the light of certain wavelengths, which are not or not present or strong enough in normal lamps. Some companies recommend the use of type SON T lamps. They are suitable for both the growth stage, as well as the flowering stage. Ballasts are necessary for these lamps. Ballast’s of 600 watts has the most favorable output of delivered light per watt. Depending on the variety we recommend using between 400 and 800 watts per m2. With insufficient light, the plant remains light-green in color and becomes unnaturally thin and protracted. The buds will also remain smaller with insufficient light.

Saving on light is stealing from yourself!

The efficiency of the lighting in the grow room can be strongly increased by covering your grow room with reflective materials. You could paint the walls with mat white paint or cover the walls with white plastic. Ensure that the room can be easily cleaned because spraying might pollute the walls quite a bit. Most sorts of your “favorite plants” remain in their vegetative (grow) state when the light cycle is maintained at 18 hours. Your “favorite plant” is a so-called short-day plant, in this we mean that the plant will start flowering when we shorten the light period. Plants are initiated into the flowering phase by shortening the day period to 12 hours on and 12 hours off per 24 hours. Your “favorite plants” that originate from the tropics do not react to changing day lengths but flower after a certain time. That is logical if you realize that a day in the tropics lasts approximately 12 hours the whole year-round. The lamp must hang at a distance from the plants that will not cause any scorching of the leaves. This distance differs from the wattage of the lamp. We recommend a distance of: 400 Watt- 45 cm; 600 Watt- 85 cm; 1000 Watt- 105 cm. Don’t hang the lamp any higher above the plants than necessary.

Carbon Dioxide

Carbon dioxide is absorbed by the plant through its pores. In small spaces, the present carbon dioxide will soon be used up. Therefore the air in the grow room has to be replenished regularly. For this, you need to buy an exhaust fan. You have to make sure however that it is powerful enough to replenish all the air at least 20 times per hour. The fan can be connected to a time clock or thermostat and/or hygrometer. To provide for an optimal gas change for the plant we also recommend placing an oscillating fan in the grow room, in order to have a constant airflow along with the plants.

In urban areas, the carbon dioxide concentration might increase to a higher value than the normal 0.03% which is 300 ppm (parts per million). From regular horticulture, we know that adding extra carbon dioxide to a concentration of 0.15% highly stimulates the
growth and the speed of photosynthesis. This results in faster and higher yields. This yield increasing effect is most powerful with intensive lighting and inert substrate cultivation, such as rock wool. Another effect that has been reported by growers is the
fact that a higher carbon dioxide concentration makes the plants less sensitive to higher temperatures.

A third effect is that there is less need to ventilate (unless the humidity is too high) because you don t depend on carbon dioxide from the outside air. In greenhouses, the exhaust gas of oil-fired central heating is conducted back into the greenhouse. To raise
the carbon dioxide concentration in grow rooms, it is usually supplied from bottles. There are two ways to provide for more carbon dioxide in the grow room.

(I) The cheapest way is to buy a pressure regulator that can be adjusted so that after ventilation (when carbon dioxide is dispelled from the room) the right amount of carbon dioxide will be released inside again. The exact quantity you need is something you have to work out yourself. You calculate this as follows: Length x Width x Height of the grow room in meters gives the volume of the room in cubic meters. One cubic meter is 1000 liters. If for instance, you want to increase the concentration from 0.03% to the required level of 0.15%, you need to add 0.12% carbon dioxide. Suppose you grow room measures 2 x 2 x 3m, which is 12000 liters. 0.12% of 12000 liters is 14.4 liters. So to this room, 14.4 liters of carbon dioxide should be added to obtain an optimal gas concentration. This needs to be done after every exhaust period. This only needs to be done during the “day period”, because the plants only use carbon dioxide when the light is on. One kilo of carbon dioxide is approximately 500 liters. So a 10-kilogram bottle contains approximately 5000 liters. This means that a grow room of 2 x 2 x 3m needs two
bottles per grow period.

(II) The second system to keep the concentration of carbon dioxide at the right percentage is by the use of a carbon dioxide meter and a computer-controlled pressure regulator. The concentration of gas is constantly measured and the computer makes sure that with a too low concentration, the right quantity of gas is added. The ventilator could also be connected to this computer. This system is not cheap but once it has been installed you don’t need to worry about it anymore.



The recommended day temperature with the cultivation of your “favorite plant” lies between 25 and 28 deg C. With higher temperatures the growth will slow down and the yield and quality will decrease (many growers experience this during summer). In the dark, other chemical reactions occur in the plant than in the daytime. A lower temperature suits them best. The recommended night temperature lies between 15 and 20 deg C. With temperatures lower than 15 deg C the growth is obstructed, lower than 10 deg C the growth stagnates, and lower than 5 deg C will damage the plant. The most ideal situation would be a grow room with both heating and air-conditioning.

The roots are especially sensitive to low temperatures. The absorption of nutrients through the roots is an active process. This means that the root needs the energy to absorb the nutrients, but also to be able to select these nutrients. The root can, to a certain
point, choose which and how much nutrient it absorbs. This process can be seriously disturbed with too low a temperature because then there is insufficient energy available for this process. Therefore you have to make sure that when watering the plants the water is approximately 23 deg C. With cultivation on rock wool the nutrient solution temperature is held constant with the use of a special twin glass sleeved aquarium heater that has a built-in thermostat.



It speaks for itself that the plant must receive enough water. Don’t forget that the water needs of a plant, in time, can strongly differ. Freshly transplanted seedlings and cuttings require less water than a flowering adult plant. It is of great importance that the plant has a well developed and healthy set of roots for the optimal absorption of water (and the nutrients that will be mentioned hereafter). Most of the water absorbed by the plant is evaporated via the leaves. By doing so the air in the grow room becomes humid.


Relative Humidity

The humidity will decrease because of the ventilation in the grow room. To measure the humidity, you need a hygrometer. The high relative humidity is very important for the seedlings at the beginning of the cycle (between 60% and 75%). In the end it is
important to keep the RH low (40% to 50%) because it could cause the buds to rot. If the humidity is too high, you need to exhaust more air. If the humidity is too low you could first try to increase it by hanging some wet (clean!) towels or sheets in the room and by often spraying the underside of the leaves (normal tap water). If this is not sufficient you might consider buying a humidifier.

Nutrients in General

For the healthy development of a plant, a number of nutrients are indispensable. The following elements are necessary: carbon, hydrogen, oxygen, nitrogen, phosphorus, sulfur, potassium, calcium, magnesium, iron, manganese, copper, zinc, molybdenum,
barium and chlorine. Carbon is being absorbed through carbon dioxide. (In carbon dioxide one particle of carbon is attached to two particles of oxygen). Hydrogen and oxygen are mainly absorbed by means of water. (In water two particles of hydrogen are
attached to 1 particle of oxygen). These matters have already been explained.

Nitrogen together with phosphorus and potassium are the main ingredients in normal fertilizers. All proteins, also the ones in the plant, contain nitrogen. All enzymes (these are matters that regulate the character and speed of the chemical reactions in the plant) are proteins. Especially chlorophyll with which the plant produces sugars (with the help of light, water, and carbon dioxide) contains many proteins and therefore a lot of nitrogen. From the previous, you might understand why nitrogen is such an important nutrient for the plant. When a plant receives too little it is first shown by the color. Because so much nitrogen is needed to make chlorophyll, a shortage will be noticed here first. The plant will become failingly light green. This fading starts first with the older leaves. BUT: when there is insufficient light it is of no use for the plant to make chlorophyll which also gives this light green color. When this is the cause, however, the leaves also tend to “reach out for the light” in their shape. With a nitrogen shortage, you don’t see this. Also with a nitrogen shortage, the plant becomes more susceptible to mycosis. With too much nitrogen the opposite will happen. The plant becomes unnaturally dark green and the growth stagnates.

Just like nitrogen, phosphorus is important for the protein chemistry of the plant, especially in the regulation processes. A shortage of it is expressed as slow growth and sometimes a purple-ish coloring of the whole leaf. The chance of a phosphorus shortage is small with the right nutrition. An excess is more likely to occur, especially with substrate cultivation, because phosphorus can accumulate in the root environment. When this happens the plant can’t absorb enough zinc so the symptoms are similar to with a lack of zinc (see Zn).

This nutrient is especially important in humidity regulation. With a potassium deficiency, symptoms of burning occur. (see page 10). With too much potassium there will be a shortage of calcium and magnesium. (see Ca and Mg). During the flowering period, the plant requires more potassium.

Magnesium is necessary for the production of chlorophyll. With a deficiency, the plant will yellow between the veins, initially in the older (strange enough not in the very oldest) leaves. Your “favorite plant” is a true magnesium lover. Too much would make the
growth stagnate, but this has never been established with cultivation.

This nutrient is “built-in” the cell walls and membranes of the plant cells. A shortage might occur in the leaves when the relative humidity is too high (and they cannot evaporate enough water), and with a potassium overdose. With a lack of calcium, the
young leaves and new buds die. The plant also becomes very susceptible to mycosis. If the calcium deficiency is being caused by too high humidity, the entire crop can be ruined in no time through molding. An overdose of calcium has never been established
with this plant.

Sulfur (S)
The plant uses sulfur to build up proteins. Overdoses or deficiency are unknown in practice.

The plant uses iron in its enzymes. When growing on soil, both overdose and deficiencies are unknown. When growing on rock wool, however, an iron deficiency might occur as a consequence of a too high pH.  An iron deficiency is easily recognized by the chlorosis of leaf tissue on the growing shoots. Leaves in the shoots have a network of green veins which stand out among the
yellow or white tissue between the veins.

The plant also uses this in its enzymes. Deficiencies and overdoses are both unknown when growing on soil. A lack might occur when growing on rock wool because of a too high pH. This is recognized by yellowing between the veins of the new leaves (but not the very newest).

Copper deficiencies are extremely rare. Be careful not to confuse this deficiency with the symptoms of over-fertilization.

Zinc is also used in the enzymes. A zinc deficiency is usually the result of an overdose of phosphorus. The symptoms are chlorosis of tissue between the veins of top shoots starting at the base of the leaf. A radial or horizontal twisting of the leaf blades in the growing shoots is a dead give away.

The plant needs boron to transport sugars. When there is a deficiency symptom first appear on the growing shoots which turn brown or gray and die. The shoots may look burnt. A good indication of B deficiency is that after the top shoot dies, actively growing side shoots start to grow but die also.

This nutrient is needed for a few important enzymes in the plant that play a role in the manufacture of nitrogen. Extremely rare, look for another cause.

One of the things you never find in other manuals is the following: We have told you before that the absorption of nutrients is an active process and that plants can, within certain limits, decide what and how much they absorb with their roots. Suppose that a
the nutrient solution contains nutrient A and nutrient B in equal amounts.

The plant grows fine but it happens to use some more of A than of B. After some time the EC has dropped and is adjusted with new nutrients that again contain equal amounts of A and B. But more has been used of A, so after adjusting, the solution contains more of B than of A. If this continues for a while the solution will contain too much of B and too little of A whereas the EC has the right value. With the EC you determine the concentration of nutrients but not WHICH nutrients.

Besides, the plant also expels certain toxins through the roots into the drainage water. For these reasons we strongly advise you not to use the drainage water a second time.



Once sprouted, the plant starts vegetative growth. This means the plant will be photosynthesizing as much as possible to grow tall and start many grow tips at each pair of leaves. A grow tip is the part that can be cloned and propagated asexually. They are located at the top of the plant, and every major internode. If you “top” the plant, it then has two grow tips at the top. If you top each of these, you will have 4 grow tips at the top of the plant. (Since it takes time for the plant to heal and recover, it is usually faster to grow 4 smaller plants and not top them at all.)

All plants have a vegetative stage where they are growing as fast as possible after the plant first germinates from seed. It is possible to grow plants with no dark period, and increase the speed at which they grow by 15-30. Plants can be grown vegetatively indefinitely. It is up to the gardener to decide when to force the plant to flower. A plant can grow from 12″ to 12′ before being forced to flower, so there is a lot of latitudes here for each gardener to manage the garden based on goals and space available. A solution of 20-20-20 with trace minerals is used for both hydroponic and soil gardening when growing continuously under lights.

Miracle Grow Patio or Rapid Grow plant food is good for this. A high P plant food such as Peter’s 5-50-17 food is used for blooming and fruiting plants when beginning 12 hour days. Epsom salts (1 tsp.) should be used in the solution for magnesium and sulfur minerals. Trace minerals are needed too if your food does not include them. Miracle Grow Patio includes these trace elements and is highly recommended. Keep lights on continuously for sprouts, since they require no darkness period like older plants. You will not need a timer unless you want to keep the lamps off during a certain time each day.

Try to light the plants for 18 or more hours, or continuously at this point. Later, if you want to mature the plants indoors, you will need to cut backlight to 12-13 hours with strict, regular uninterrupted darkness to get plants to produce flowers. Bend a young plant’s stem back and forth to force it to be very thick and strong. Spindly stems can not support heavy flowering growth. An internal oscillating fan will reduce humidity on the leave’s stomata and improve the stem strength as well.


Miracle Grow Patio (contains trace elements) _ teaspoon
Epsom salts 1 teaspoon
Lime (if not added to medium) 1 teaspoon
Human Urine 1/4 cup
Oxygen Plus Plant Food (OPTIONAL) 1 teaspoon

This mixture will ensure your plants are getting all major and minor nutrients in solution, and will also be treating your plants with oxygen for good root growth, and potassium nitrate for good burning qualities. Another good growth phase mix is 1/4 tsp. Peter’s 20/20/20 fertilizer per gallon of water, with trace elements and oxygen, added.


The plant will be induced to fruit or flower with dark cycles of 11-13 hours that simulate the oncoming winter in the fall as the days grow shorter. As a consequence, it works out well indoors to have two separate areas; one that is used for the initial vegetative state and one that is used for flowering and fruiting.

There is no other requirement other than to keep the dark cycle for flowering very dark with no light interruptions, as this can stall flowering by days or weeks. Once a plant is big enough to mature (18″-18 feet), dark periods are required for most plants to flower and bear fruit. This will require putting the lamp on a timer, to create regular and strict dark periods of uninterrupted light.
Give flowering plants high P plant food and keep them on a strict light regimen of 12 hours, with no light, or no more than a full moon during the dark cycle. 13 hours light, 11 dark may increase flower size while still allowing the plant to go into the flowering mode. Use less light, longer dark periods to speed maturity toward the end of the flowering cycle.

Two shelves can be used, one identical to the other, if strictly indoor gardening is desired. One shelf’s lights are set for 12-13 hours, and one is lit continuously. Plants are started in continuous light and are moved to the other shelf to flower to maturity after several weeks. This flowering shelf should be bigger than the “starting” or “vegetative” shelf so that it can accommodate larger plants. Or, some plants can be taken outside if there is not enough space on the flowering shelf for all of them near harvesting.

A light-tight curtain can be made from black vinyl, or other opaque material, with reflective material on the other side to reflect light back to the plants. This curtain can be tied with cord when rolled up to work on the garden and can be velcroed down in place to make sure no light leaks in or out. If the shelf is placed up high, it will not be very noticeable and will fit in any room. Visitors will never notice it unless you point it out to them, since it is above eye level, and no light is being emitted from it.
Flowering plants like very high P level foods, such as 5-50-17, but 10-20-10 should be adequate.

Nutrients should be provided with each watering when first flowering. Trace elements are necessary too; try to find foods that include these, so you don’t have to use a separate trace element food too.


_ strength high P plant food, such as 4-12-6, or 5-50-17, etc.
1 tsp. Epsom salts
1 tsp. lime (if not part of the medium)
1 tsp. Oxygen Plus Plant Food (Optional)
_ tsp. Trace Element food

I cannot stress enough that during the flowering phase, the dark period should not be violated by normal light. It delays flower development due to hormones in the plant that react to light. If you must work on the plants during this time, allow only as much light as a very pale moon can provide for less than 5 minutes. Keep pruning to a minimum during the entire flowering phase. Bring the dark period down to 10 or 8 hours to hasten maturity after flowering for 4-6 weeks.

A green light can be used to work on the garden during the dark period with no negative reactions from the plants. These are sold as nursery safety lights, but any green bulb should be OK. Flowering plants should not be sprayed often as this will promote mold and rot. Keep humidity levels down indoors when flowering, as this is the most delicate time for the plants in this regard. Early flowering is noticed 2-3 weeks after turning back the lights to 12 hour days. Look for 2 white hairs emerging from a small bulbous area at every internode. This is the easiest way to verify females early on. You can not tell a male from a female by height, or business.

After 4-6 weeks of turning back the lights, your plants will be covered with these white pistils emerging from every growing tip on the plant. It will literally be covered with them. These are the mature flowers, as they continue to grow and cover the plant. Some plants will do this indefinitely until the lights are turned back yet again. At the point, you feel you’re ready to see the existing flowers become ripe (you feel the plant has enough flowers), turn the lights back to 8-10 hours. Now the plant will start to ripen quickly and should be ready to harvest in 2-3 weeks.

Look for the white hairs to turn red, orange or brown, and the false seed pods (you did pull the males, right?) to swell with resins. When most of the pistils have turned color (~80%), the flowers are ripe to harvest. Don’t touch those buds! Touch only the large fan leaves if you want to inspect the buds, as the THC will come off on your fingers and reduce the overall yield if mishandled.


Most growers report that a hydroponic system will grow plants faster than a soil medium, given the same genetics and environmental conditions. This may be due to closer attention and more control of nutrients, and more access to oxygen.
The plants can breath easier, and therefore, take less time to grow. One report has it that plants started in soil matured after hydroponic plants started 2 weeks later! Fast growth allows for earlier maturation and shorter total growing time per crop.
Also, with soil mixtures, plant growth tends to slow when the plants become root-bound. Hydroponics provides even, rapid growth with no pauses for transplant shock and eliminates the labor/materials of repotting.

By far the easiest hydroponic systems to use are the wick and reservoir systems. These are referred to as Passive Hydroponic methods because they require no water distribution system on an active scale (pump, drain, flow meter, and path). The basis of these systems is that water will wick to where you want it if the medium and conditions are correct. The wick system is more involved than the reservoir system since the wicks must be cut and placed in the pots, correct holes must be cut in the pots, and a spacer must be created to place the plants up above the water reservoir below. This can be as simple as two buckets, one fit inside the other, or a kiddy pool with bricks in it that the pots rest on, elevating them out of the nutrient solution.

I find the wick setup to be more work than the reservoir system. The initial setup is a pain with wicks, and the plants sit higher in the room, taking up precious vertical space. The base the pot sits on may not be very stable compared to a reservoir system, and a knocked over plant will never be the same as an untouched plant, due to stress and shock in recovery. The reservoir system needs only a good medium suited to the task, and a pan to sit a pot in. The pots are filled with a lava/vermiculite mix of 4 to 1. This medium will store water but has excellent drainage and air storage capacity as well. It is also reusable to the extent it can be recaptured from harvested plants.

Use small size lava, 3/8″ pea size, and rinse the dust off it first. Wet the vermiculite (dangerous dry, wear a mask) and mix it into pots. Square pots hold more than round. Vermiculite will settle to bottom after repeated watering from the top, so only water from the top occasionally to leach, and put more vermiculite on the top than the bottom. The pan is filled with 1 _ – 3 inches of water and allowed to recede between waterings. Every two weeks the plants are watered with no nutrients from the top to leach out mineral deposits. If you go away, reservoirs made of 2-liter soda bottles inverted into a container to fit, and hosed over to the pans with a water level mark and position similar to a pet watering dispenser can be made to keep the plants watered for 2-3 weeks at least.

One really great hydroponic medium is floral foam. Stick lots of holes into it to open it up a little, and start plants/clones in it, moving the cube of foam to lava/perlite later for larger growth stages. Foam rubber, or most types of porous foam, as well as rock wool, will be good for this as well. Many prefer floral foam, as it is inert, and adds no PH factors. It’s also pretty cheap if you buy the generic brands. Planting can be made easier with hydroponic mediums that require little setup such as rock wool. Rock wool cubes can be reused several times, and are premade to use for hydroponics.

Some advantages of rock wool are that it is impossible to overwater and there is no transplanting. Just place the plant’s cube on top of a larger rock wool cube and enjoy your extra leisure time. Some find it best to save money by not buying rock wool and spending time planting in soil or hydroponic mediums such as vermiculite/lava mix. Pearlite is nice since it is so light. Pearlite can be used instead of or in addition to lava, which must be rinsed and is much heavier. But rock wool has many advantages that are not appreciated until you spend hours repotting, take a second look. It is not very expensive, and it is reusable. It’s more stable than floral foam, which crunches and powders easily. Rock wool holds 10 times more water than soil, yet is impossible to over-water because it always retains a high percentage of air. Best of all, there is no transplanting; just place a starter cube into rock wool grow cube, and when the plant gets very large, place that cube on a rock wool slab.

Since rock wool is easily reused over and over (with sterilization), the cost is divided by 3 or 4 crops and ends up costing no more than vermiculite and lava, which is much more difficult to reclaim, sterilize and reuse (repot) when compared to rock wool. Vermiculite is also very dangerous when dry, and ends up getting in the carpet and into the air when you touch it (even wet) since it dries on the fingers and becomes airborne. Rock wool’s disadvantages are relatively few. It is alkaline PH, so you must use something in the nutrient solution to make it acidic (5.5) so that it brings the rock wool down from 7.7 to 6.5 (vinegar works great.) And it is irritating to the skin when dry, but is not a problem when wet.

Hydroponics should be used indoors or in greenhouses to speed the growth of plants, so you have more buds in less time. Hydroponics allows you to water the plants daily, and this will speed growth. The main difference between hydroponics and soil growing is that the hydroponic soil or “medium” is made to dry quickly, and drain well so that there are no over-watering problems associated with continuous watering.

Also, hydroponically grown plants do not derive nutrients from the soil, but from the solution used to water the plants. Hydroponics allows you to use smaller containers for the same given size plant when compared to growing in soil. A 3/4 gallon pot can easily take a small 3′ hydroponically grown plant to maturity. This would be difficult to do in the soil since nutrients are soon used up and roots become cut-off from oxygen as they become root-bound in soil. This problem does not seem to occur nearly as quickly for hydroponic plants since the roots can still take up nutrients from the constant solution feedings, and the medium passes on oxygen much more readily when the roots become bound in the small container.

Plant food is administered with most waterings and allows the gardener to strictly control what nutrients are available to the plants at the different stages of plant growth. Passive hydroponics is easy with a reservoir system. Only a pot filled with the
correct low-moisture medium and a water tray to sit it in are needed. No pumps, hoses, or other apparatus is required. The pot is placed in the pan, and watered from the top or directly into the pan. Holes in the bottom and side near the bottom of the pot allows water into the pot and is wicked up to the roots by the vermiculite. A pot filled with lava and vermiculite should be moist at the top after water is added to the pan. Kitty litter pans can be purchased at five and dime stores on sale for as little as $1 each, and make great water pans. 12-16 cut-down paper milk cartons will fit in each pan.

A small closet can easily hold a hundred plants at a time when starting and can hold 12-48 for harvesting. Watering can be automated to some degree with simple and cheap drip system apparatus, so take advantage of this when possible. Hydroponics will hasten the growing time, so it takes less time to harvest after planting. It makes sense to use simple passive hydroponic techniques when possible. Hydroponics may not be desirable if you’re growing outdoors unless you have a greenhouse.

CAUTION: it is necessary to keep close watch of plants to be sure they are never allowed to dry too much when growing hydroponically, or roots will be damaged. If you will not be able to tend to the garden every day, be sure the pans are filled
enough to last until next time you return, or you can easily lose your crop.

Plants in soil are much easier to care for in this respect since moisture storage crystals can be added to the soil to buffer water for long periods between watering. If you need to, it is possible to automatically regulate the water level in hydroponic pans by toilet bowl float in a master reservoir, or using a gurgle bottle that holds water and adds it as the level recedes, like a pet watering bottle used for dogs and cats. Also, a pump can be put on a timer to add water to the pans.

If you’re watering every day hydroponically, you may be able to water twice a day if you increase ventilation and make sure the plants don’t build up too much humidity. You can water more often (and thus increase plant growth) if you have slightly warmer temperatures, less water retention in your medium, and better drainage, or all of the above. What counts is that you’re watering more often, but still allowing the medium to dry between waterings.

Change the solution every month if you’re circulating it with a pump, but the reservoir system does away with this problem. Just rinse the medium once a month or so to prevent salts build up. Change plant foods often to avoid deficiencies in the plants. I recommend using 2 different plant foods for each phase of growth, or 4 foods total, to lessen chances of any type of deficiency.
Change the solution more often if you notice the PH is going down quickly (too acid). Due to cationic exchange, the solution will tend to get too acid over time, and this will cause nutrients to become unavailable to the plants. Check PH every time you water.

Watch out for alga and higher humidity’s in hydroponics when watering plants. A layer of gravel at the top of the pot may help since it will dry very quickly. Make sure you’re not over-watering the plants. Allow them to almost dry out after each watering.

When the first signs of flowering are visible, you can change over to a flower nutrient. The EC can also be increased to approx. 2.2. Increase the EC by 0.1 per day. The pH remains at 5.8. It is advisable to occasionally (e.g. every one or two weeks) flush the slabs through with clean tap water. This prevents the buildup of harmful salts. Adjust this tap water with pH up or down to the normal pH-level of 5.8. It is advisable, from now up to and including the last day, that regular checks of all the values are carried out. For example, the drainage water gives us a good indication of the needs of the plant. Therefore, frequently measure the amount, its pH, and EC-values. If necessary increase the time of watering periods. In order to obtain an accurate measurement in the slab, you are best off using a 140ml syringe.

Remove the water sample from the slab where the roots are. For taking water samples use a large syringe with a 0.5mm stainless steel needle. The optimal pH in the slab is around 6.0. This may not vary more than 0.5pH. (e.g. 5.5-6.5). The EC in the slab may be a max. of 0.5 higher than in the nutrient reservoir. The week before harvesting, stop with all nutrients, and only give tap water, without pH correction. This forces the plant to use up all its nutrients-reserves, this considerably improves the sweetness and taste.




– Water demand by crops is greatest during the light cycle.
– Unless there is a plentiful supply of water, the plant cannot take up CO2 – the
breathing pores will close.
– Watering at end of the light cycle, or in darkness, creates high humidity levels in
the garden. This can encourage disease or pest problems to gain a foothold in the


– Coldwater causes slow growth.
– Hot water damages roots. This reduces the ability of the plant to take up food and water
– and diseases may attack the damaged roots, invading the plant. Even very warm solutions of water and fertilizer can damage roots, especially if the nutrient solution is strong (over 1000 PPM).


– The fertilizer solution can cause root damage to dry roots, even if it is mixed at normal strength. Water a dry plant well (with plain water) an hour before fertilizing.


– Outdoor fertilizers can contain high levels of a nitrogen source called ammonia
– this is too active a form of nitrogen for hydroponics crops in containers. In an outdoor garden, armies of bacteria in the soil quickly break down ammonia nitrogen into nitrates
– a milder form of nitrogen
– for plant uptake and use.

Outdoor fertilizers often contain only three of the eleven required nutrients that plants use. Gardeners hope the outdoor soil can supply these missing elements. Hydroponic foods contain all the required minerals for best plant growth and crop yield.


– pH affects the availability of nutrients – if the root zone is very acidic or alkaline, some minerals will bond together and become unavailable to the roots.


– Well-aerated nutrient solutions allow roots to take up fertilizers easier and faster.
– Adding air to water or nutrient solutions reduces disease problems. Hydrogen
peroxide can be added to water to actually kill diseases, using the oxygen that peroxide releases into the water to destroy disease cells.


– The first time you use any new fertilizer, mix it only half-strength.
– Mixing instructions on a fertilizer assume plants are healthy, free of pests and diseases, and actively growing in full sun, with lots of fresh air, and with moderate temperatures (about 30 degrees C). If all these conditions are in place, plants can
use full-strength nutrient mixes.
– If plants have a disease or pest problems, poor air movement, bad light, or very high (or low) temperatures, use only half-strength fertilizers while you correct the problem.
– For fast-growing crop plants with excellent growing conditions, the use of additional CO2 and growth hormones (“Growth Plus”) can create situations where plants might be able to make use of stronger fertilizer solutions than the manufacturer’s recommended mixing rate. Always use a food strength meter to be sure that gradual increases in nutrient concentrations allow plants to adapt to stronger food levels. If you decide to try increasing your food strength, do it gradually, by 200 PPM increases, allowing two or three days between increases. Keep a close watch on crops to spot signs of nutrient stress of damage. Flush roots
well with plain water (or water/power thrive solution) and reduce food strength if our plants show signs of over-feeding.
– During periods of slow growth, reduce the strength of fertilizers.


– “Fertilizer build-up” refers to situations when foods accumulate near the roots, burning them and stressing the plant. Some grow mediums
– the soilless mixes
– tend to hold fertilizers and need different treatment than hydro corn or rock wool crops to avoid build-up of fertilizers in the potting mix. Feed plants in potting soils once, then use plain water the next time
– by alternating feeding and watering, we avoid fertilizer build-up, since water re-dissolves the food that was held by the
potting soil, making it available again to the roots.
– In hot weather, feed crops in potting soils once, then water twice as needed before the next feeding.


– Roots spread through potting soil until they reach the container. Then the roots wind around the inside of the flower pot, forming a web around the outside of the potting soil.
– Rootbound plants need re-potting. Sure signs of root-bound conditions are:
Soil dries very quickly between waterings. Soil shrinks away from containers, leaving an air gap between the soil and the nursery pot Soil “collapses”, forming a bowl-shaped surface, often with a crust.
– Re-pot before signs of root-bound conditions occur.
– Remove container from soil occasionally to check on root conditions
– Re-pot plants when roots have reached the outer surface of the potting soil and are just starting to wind around the inside of the container. Roots spread easier into the new soil. Plants with thick, winding roots spread slowly into large containers, and the web of roots can interfere with water movement through the potting soil. Your new soil could be moist, but the inner core of soil will stay dry, causing plant stress.
– Re-pot to final pot size at least two weeks before starting the flowering or crop
production stage.


– After transplanting to larger containers
– During periods of active growth (green growth, flowering, crop production).
– Use every 10 – 14 days.
– Mixing rage: one capful / one liter (foliar spray)
OR one capful / five liters (root soak)


– When crops are “shifting gears” – changing into a new growth stage:
– plants adjusting to higher light levels (new transplants). Plants changing from green growth to flowering cycle, especially with reduced day length. (See “Shifting Gears” information sheet for more hints on getting through this period of change.)
– During high-temperature periods, or when crops have disease or pest problems.
– When plants are growing in low light level conditions.
– During the final two weeks of crop production, as growth slows.


– For new cuttings and seedlings:
To pre-moisten grow mediums To “water in” new cuttings and seedlings. For misting and watering cuttings and seedlings until established.
– For fast recovery from stress:
Plants recovering from disease or pest problems Plants recovering from heat or water stress


– The closest minimum distance between lamps and crops is determined by temperature, since plants grow best at 30 degrees C = 85 degrees F. Since heat levels will vary from one garden to the next, the minimum distance in your garden may be different from another garden with different light levels, air movement, etc.

To find the minimum (closest) distance for your garden:
– Use a small thermometer, mounted at the top of your plants.
– When the thermometer gives a continuous reading of 30 degrees C, the lamp is at
its closest possible position to the crop – note this distance so you’ll remember to
keep moving the reflector up as crops grow, to keep the best temperature for your plants.
– Once you have learned how close you can safely have the lamp from your crop,
move lamp away from the crop until all plants are well-lit.
– Fix the lamp into this position. Maintain at least the minimum distance from the
crop by moving the lamp higher as plants grow taller.
– High temperatures cause SLOW growth and STRESS plants!


Importance of AIR

Air is the most versatile, yet unappreciated, worker in the garden. When gardeners understand how many chores a little air can do, they can put it to better use to make their gardens healthier and more productive.

Let’s start with air “feeding” plants. Everyone knows that plants grow from fertilizers, right? Guess again! Almost HALF the dry weight of plants is carbon, taken from air! Another 42% of your plants is oxygen! All those fertilizers you’ve been mixing and feeding to your corps? They only make up about 2% of your crop’s dry weight! Considering air only has 300-400 parts per million of carbon dioxide (0.03%), we can concluded two things: plants are pretty good at grabbing CO2 from the air, and they can use all the fresh air they can get!

Air is your greatest ally in the war against bugs and disease! Moving air can blow insects off your crops, and interfere with their meal-times. Who can eat in a hurricane? Air movement also lays havoc with egg-laying and the growth of baby bugs in your garden. Bugs want still, moist air – and if they can’t get it in your garden, they’ll go somewhere else! This is one good reason why we emphasize good spacing between plants, oscillating fans, an air intake source and good exhaust fans. Let someone else get the bug problem!

Air movement through the garden helps keep diseases in check, by keeping humidity levels from climbing to unhealthy levels. Diseases multiply quickly instill, moist air, and use any water on the leaf as an entry point to damage leaves. If you can run ALL your fans 24 hours a day (without chilling your garden) you’ll help your plants stay healthy and disease-free.

Air fights disease in the root zone, too. The worst diseases need waterlogged conditions to multiply and attack roots – air is their poison! (talk about a safe, cheap fungicide!) Want to keep roots – and plants – healthy? Don’t overwater, and
let air work for you in the root zone.

How can air make crops take up water and food faster and better? In two ways: first, air in the root zone means healthy, growing roots eater to work hard supplying the top growth with food and water. Second, good air movement through plants draws lots of food and water up from the roots. How? To understand this, you’ll want to meet the STOMA, a tiny breathing pore on the underside of a leaf. This stoma’s a busy place – a sort of grand central station of the plant world.

Carbon dioxide and oxygen are coming and going through this tiny opening, and this is where water vapor drifts out of the leaf into the air. Lots of water vapor – if your crops used 100 gallons of water and food mix last week, they “transpired” 99 gallons of water out of this breathing pore, keeping only one gallon for actual growth! It sounds wasteful, doesn’t it? But plants have a purpose in handling all this water: as a drop of water evaporates and drifts out of the leaf, it yanks another drop of food and water into the roots. In this way, plants suck water and food into the roots and draw them up the stem to the leaves, concentrating the minerals from the fertilizer mix in the leaves for use by the plant. Evaporation of the excess water also cools the leaf, keeping it at an efficient working temperature.

Another important use of this water movement: it keeps air spaces in the leaves moist so CO2 can dissolve into the damp air – a necessary first step for uptake and use of CO2 by the plant. When we supply good air movement through the garden, we help
to speed everything up – CO2 uptake, food and water movement into the plant, utilization of minerals by the leaves – in other words, we speed up GROWTH! Air isn’t a riddle any more – put it to work for you and your garden, and it will prove its usefulness to the health and yield of your crops.


Creating Good Growing Conditions in the Garden

Temperature: If plants could be fussy about one main growing condition, it would be temperature. Aside from drying out the roots completely (not recommended unless you enjoy funerals !) the quickest way to create problems in your greenhouse is to mess with your plant’s temperature.

The bad news is: Letting the thermometer climb – or – drop by only a few degrees can make plants clench up and stop growing.
The good news is : We know what they like. Here is a list of recommended temperatures for different stage of
growth in the garden.

Please note: The listed temperatures refer to TEMPERATURE AT THE TOP OF PLANT not the floor, wall, or outside!
Use a small thermometer on a bamboo stake for accuracy!

SEEDLINGS AND CUTTINGS 21 C (70 F) Day and night
GREEN GROWTH 30 c (85 F) days 18-21 C (65-70 F) Nights
15-18C(60-65F) Nights
ROOTS (Green Growth and Crop Production) 21C (70F)

Hydrogen Peroxide

Do you know how to use it?

Most distributors of 35% food-grade Hydrogen Peroxide recommend using 3-5 ml per gallon of solution. Here is what they don’t tell you, they do not know how it works in hydroponic situations and how it relates to nutrient solutions and delicate root hairs.

When Hydrogen Peroxide is added to water it creates a certain level of Ozone, Ozone will, having the opportunity, react with any organic compounds that are present and this is called oxidation. Hydrogen Peroxide is water with an extra oxygen molecule causing it to be unstable and when you add it to water H202 + H20 = H403, the 03 in the equation is ozone and requires oxidation to break it down into 02 which is stable.

The directions for use in hydroponics is 1 ml per gallon of water without nutrient present in the water, if you add Hydrogen Peroxide to your nutrient solution then you run the risk of the ozone reacting with the mineral salts allowing them to fall out of solution. Do not use more than this because it may break down the outer layer of the root hair making it susceptible to root disease which is in many cases the very reason you are using it. When used properly it will enhance the oxygen content of your solution. Another thing I need to mention is that when you add Hydrogen Peroxide to your water let it stand for an hour before you add your nutrient so as not to get any reaction.

1ml per gallon
let stand _ hour
add only to water.


Various growing media can be used in hydroponic systems. However, any system must have the following four qualities:

-sufficient support for the plants
-appropriate distribution of air, since roots
-need oxygen and respire other gasses, such
-as carbon dioxide
-maximum water availability for the plant roots
-accessible nutrient solution with consistent
-chemical characteristics

Liquid (non-aggregate) Hydroponic Systems

Deep Flow Hydroponics 

The classic hydroponic system, where plants are supported so that their roots hang into a nutrient solution, is generally called “deep flow hydroponics”. This system is appropriate for hobbyists and large scale production of leafy vegetable crops. The system consists of horizontal, rectangular-shaped tanks lined with plastic. The nutrient solution is monitored, replenished, recalculated, and aerated. Commercial facilities are now quite popular in Japan. The rectangular pools act as frictionless conveyor belts where large, moveable floats of plants (lettuce) can be transported from transplant to harvest.

Nutrient Film Technique

A modification of the deep flow system is called “nutrient film technique”, where a thin film of nutrient solution flows through plastic-lined channels, which contain the plant roots. The walls of the channels are flexible; this permits them to be drawn together around the base of each plant, excluding light and preventing evaporation. For lettuce production, the plants are planted through holes in a flexible plastic material that covers each trough. The nutrient solution is pumped to the higher end of each channel and flows by gravity past the plant roots to catchment pipes and a sump. The solution is monitored for the replenishment of salts and water before it is recycled. Capillary material in the channel prevents young plants from drying out, and the roots soon grow into a tangled mat. This method is mainly used for tomatoes.


Aeroponics is another technique, where nutrient solution is sprayed as a fine mist in sealed root chambers. The plants are grown in holes in panels of expanded polystyrene or other material. The plant roots are suspended in
midair beneath the panel and enclosed in a spraying box. The box is sealed so that the roots are in darkness (to inhibit algal growth) and in saturation humidity. A misting system sprays the nutrient solution over the roots periodically. The system is normally turned on for only a few seconds every 2-3 minutes. This is sufficient to keep
roots moist and the nutrient solution aerated. Systems were developed by Dr. Merle Jensen at the University of Arizona, for lettuce, spinach, and even tomatoes, although the latter was judged not to be economically viable. In fact, there are no known large-scale commercial aeroponic operations in the United States, although several small
companies market systems for home use.


Aggregate Hydroponics

In aggregate hydroponic systems, a solid, inert medium provides support for the plants. As in liquid systems, the
nutrient solution is delivered directly to the plant roots. Aggregate systems may be either open or closed, depending
on whether surplus amounts of the solution are to be recovered and reused. Open systems do not recycle the nutrient
solutions; closed systems do.

In most open hydroponic systems, the excess nutrient solution is recovered; however, the surplus is not recycled to the plants but is disposed of in evaporation ponds or used to irrigate adjacent landscape plantings or windbreaks. Because the nutrient solutions
are not recycled, such open systems are less sensitive to the composition of the medium used or to the salinity of the water. These factors have generated experiments with a wide range of growing media and the development of more cost-efficient designs for containing them.

There are numerous types of media used in aggregate hydroponic systems. They include peat, vermiculite, or a combination of both, to which may be added polystyrene beads, small waste pieces of polystyrene beads, or perlite to reduce the total cost. Other media such as coconut coir, sand, sawdust, are also common in some regions of the world.

For growing row crops such as tomato, cucumber, and pepper, the two most popular artificial growing media are rock wool and perlite. Both of these media can be used in either closed or open systems (gravel is not recommended as an aggregate in either
system). Both media are lightweight when dry, easily handled and easier to steam-sterilize than many other types of aggregate materials. Both can be incorporated as a soil amendment after crops have been grown in it.

Rock wool, or stone wool, is produced from basalt rock and can come as spun wool, resembling fiberglass, or it can be granulated, offering an alternative to perlite and vermiculite in terms of water holding capacity and aeration. Stone wool has a high pH, generally greater than 8.0, however, it has essentially no buffering capacity, meaning it will not affect the pH of the nutrient solution nor will it affect any other media it is mixed with, such as peat moss (which has a pH of 3.8 to 4.5). Stone wool can be purchased in prepackaged “slabs (commonly 15 x 7.5 x 100 cm long), ready to use, or as bulk granules for those growers who wish to mix their own soil-less media.

Perlite is usually bagged in opaque white bags with drip irrigation tubes at each plant and drainage slits in the bags. Perlite is an inert media providing excellent aeration and water holding capacity. As in rock wool, it can be steam-sterilized, re-bagged and
reused several times.

When both perlite and rock wool are used as closed systems, great care must be taken to avoid the buildup of toxic salts and to keep the system free of nematodes and soil born diseases. Once certain diseases are introduced, the infested nutrient solution
will contaminate the entire planting. In addition to the common practice of sterilizing the re-circulating solution, there is current research exploring the use of surfactants to control certain root diseases. Such systems can be capital intensive because they
require leak-proof growing beds as well as subgrade mechanical systems and nutrient storage tanks.


Understanding lighting can be very confusing for the beginner … we are here to help make it simple. Incandescent bulbs, like the one in your bedside lamp, create light by passing an electrical current through a very fine wire. Resistance in the wire causes it to heat up and glow.

Fluorescent tubes and low-pressure sodium lamps pass an electrical current through gaseous vapor under low pressure. Fluorescent tubes are very good for seedling and cuttings. Fluorescents can be kept very close to the leaf canopy without fear of scorching.
These can be raised as the plants grow.

If your plants require medium-high, or high light levels fluorescents are not recommended. Low-pressure sodium lamps and mercury vapor lamps are of little value in the case of indoor gardening. Restrict their use to illuminating parking lots.
High-Intensity Discharge or H.I.D. lamps produce light by passing an electrical current through vaporized gas under high pressure.

The different gases or materials contained in the arc tube dictate the colors of the spectrum that the light will produce.


When deciding upon what light source you want to use, you must consider the plants’ needs. The blue-violet and red-orange segments of the visible light spectrum are the most important for photosynthesis and chlorophyll production. Red-orange light will encourage flowering and stem elongation. Light strong in the blue-violet spectrum will keep plants short and bushy with short internodal space.

In combination the two will produce more balanced growth. Metal Halide or Multi Vapor H.I.D. lamps provide the most complete spectrum for plant growth from a single source in absence of actual sunlight. Metal Halide lamps produce a decent amount of light energy in both the blue-violet and red-orange ends of the spectrum but, leaning slightly towards blue-violet as the predominant area of spectral energy. Metal Halides can be used for both vegetative and flowering stages.

A definite improvement upon the standard ‘white’ metal halide is the new Daylight Full Spectrum bulb by Duraguard. This bulb illuminates a very definite blue spectrum resulting in very healthy vegetative growth, with short internodal spacing. Since this bulb
has a balanced spectrum it would be a perfect bulb for a one lamp operation. Available in both 400 and 1000 Watt.

High-Pressure Sodium or HPS lamps produce light energy weighted toward the red-orange area of the spectrum. Many growers use these lamps for all stages of growth, unless natural sunlight is available we would only suggest their use during flower initiation and development periods. There is a new strain of HPS bulbs that have an augmented blue segment (30% or more) making them a worthwhile choice for all growing periods.

For those who have metal halide systems and want to add or change to high-pressure sodium lamps for flowering, there are Retrofit High-Pressure Sodium Lamps available that are compatible with a metal halide ballast. The definite advantage that the retrofit bulbs have over conventional H.P. S. bulbs, is that you can use metal halides for strong vegetative growth as they are predominant in the blue-violet spectrum and high-pressure sodium lamps, which are high in the red- range spectrum for flowering. Available in both 360 and 940 Watt.

We hope this information will help you make an educated choice in purchasing your next lighting system.


Fresh air is very important.

Fresh air is at the heart of all successful indoor gardens. In the great outdoors, the air is abundant and almost always fresh. The level of C02 in the air over a field of rapidly growing vegetation could be only a third of normal on a very still day. Soon the wind blows in the fresh air. Rain cleanses the air from dust and pollutants.

The ecosystem is always moving. When plants are grown indoors the natural balance that is present out of doors must be achieved indoors by way of fresh air ventilation. You must take the task of bringing in fresh air seriously or else your green thumb is going to wilt and turn brown.

Fresh air is inexpensive and easy to find. An exhaust fan is the main tool used to satisfy this need. In order to have a good flow of air through your growing environment, adequate air circulation and ventilation are necessary. Indoors, fresh air is one of the most commonly overlooked factors in contributing to a plentiful harvest.

Experienced gardeners realize the importance of fresh air and take care in setting up proper air movement. Three factors affect air movement: stomata, ventilation, and circulation.

STOMATA are microscopic pores which are located on the undersides of the leaves. These stomata regulate the flow of gasses into and from the plant. These can get clogged with dust, filmy residues, pollen, etc… So it is very important to have air movement to keep these pores clean and free.

CIRCULATION if the air is completely still, plants will tend to use all of the C02 next to the leaf surface. When this air is used and no fresh air is forced into its place, dead air space forms stifling the stomata, slowing growth. Air also stratifies with the warm air rising and the cooler air settling towards the bottom of the room.

All of these potential problems are avoided by opening a door or window and installing oscillating fans. Air circulation is important for insect and fungus prevention. Mold spores are present in all grow rooms.

VENTILATION an average l0′ x l0′ foot vegetable garden will use from 10 to 30 gallons of water per week. Where does all this water go? It transpires and evaporates into the air. So basically, gallons of water will be held in the air. If this moisture is left in a small room, the leaves will get limp, transpiration will slow (remember the flow of water through the plant helps keep it erect) and the stomata will be stifled. This moisture must be replaced with dry air that lets the stomata function properly. A vent fan that pulls air out of the grow room will do the job.

Successful indoor gardeners know that a vent fan is as important as water, light, heat, and fertilizer. In some instances it is more important. All greenhouses have large ventilation fans. It is sometimes said that the person with the most fans wins. Vent fans are rated by the number of cubic feet of air per minute (cfm) they can replace or move. Buy a fan that will replace the volume (cubic feet) of the grow room air in about 5 minutes or less. The air that is pulled out is immediately replaced by fresh air which is drawn from little cracks under the doors or window sills. If a grow room is sealed tightly then an intake fan will probably be necessary to bring in the fresh air.

A vent fan is able to pull air out of a room many times more efficiently than a fan is able to push it out.

To calculate the room size multiply width by height this will give you the total cubic footage of your room for example 10 by 10 by 8 = 800 cubic feet. Remember that you want your fan to exchange the air within 5 minutes so for a room that is 800 cubic feet a fan that is capable of moving 160 cfm is needed.


Our Recipe for plant ‘Rocket Fuel’
In Order:

1 Liter of water at room temperature with a PH at 6.3 in a misting bottle.
Add 16 drops Hyper Oxygen. Hyper Oxygen is a 35% food-grade Hydrogen Peroxide to remove any chlorine and increase the level of oxygen availability in water, improving nutrient uptake, and effective use in plants. Also destroys harmful bacteria and viruses.

Add 36 drops Agri 2. Agri 2 is an extremely effective wetting agent ensuring plant tissue penetration, especially when misting plants with waxy or hairy leaves. Also contains an antifoaming agent.

30ml (lOz) Earth Food. Earth Food is a 2 part product, first being catalyst altered water, changing the structure of molecules in water. Your water will now form attractions with free electrons, helping better serve water’s role as a transportation, cleansing, and absorption mechanism within your plant’s circulatory system. Second, it contains activated Carbon, Amino Acid. organic trace
minerals and other desirable ingredients obtained from Lignite (the fossil remains of plants grown 50 million years ago).

5ml (3ml min. To 10 ml max.) Growth Plus. Growth Plus is the main ingredient and the best-kept secret in the industry. It is a very concentrated solution of natural growth hormones with cytokinin being the main one. This product is dynamite just on its own.

30ml (15 ml min. To 60 mi max.) Sea Mix. Sea Mix is a concentrated solution of sea plant (Ascopilyum nodosum) and Sea fish processed together for effective foliage feeding of plants. Sea Mix feeds your plants with a healthy supply of micronutrients from the sea plant and macronutrients (N-P-K) rich in sea fish.

NOTE A: The above mix is then lightly misted covering the whole plant every 2 – 3 weeks and no more than once a week during active growth. Foliage feed before 11:00 am or after 4:00 pm. It is important to note that University studies show foliage
feeding to be about 10 times more efficient than dry fertilizers and nutrients are immediately made available to the plant.

NOTE B: To use the above as a watering solution dilute 3 to 4 times.

NOTE C: Only mix up enough to be used within 48 hours. Also, 5ml is equal to 1 teaspoon.

NOTE D: All of the above products are of the highest quality and at the same concentration as manufactured. Altering the above recipe is at your own risk. Remember “more is not always better”.


Light Energy for Plant Growth


Plant Development is dependent on the specific spectrums of the light source and the usable light energy Only 37% of the energy in sunlight is within the wavelength (colors) useful for photosynthesis, while 62.4% is infrared (thermal energy) and the remaining 0.6% is ultraviolet. Photosynthesis is the plant leaf is powered by 1% of the sunlight that falls on the plant, 10% of the sunlight is
reflected and 10% passes through the leaf. The leaf will retain 80% which is used for transpiration.

Some of the light is re-radiated, while the fraction that remains is used for building food from the carbon dioxide, minerals, and water. For photosynthesis, the most important spectrums of the light are blue and red. Germination, flowering, and stem growth are influenced by red to far-red. In artificial environments, it is important to keep these factors in mind when programming the light source for the plant’s life cycle.

For the associated light, spectrum consults your bulb’s manufacturer. Useable light energy for plant growth is measured in Micro-Einstein’s ( micro-mols of photons per meter squared per second). The sunlight reaching a plant is approximately 2,200 micro-Einstein’s on a cloudless day and 170 micro-Einstein’s on a cloudy day.

For indoor growing, under artificial lighting, a range of 395 to 500 micro-Einstein’s is considered by experts to be minimal for plant growth. Note: The higher the bulb wattage the further away the plant must be from the light source to prevent the plant from transpiring too quickly. Thus, the further the plant is from the light source the less available useable energy is delivered to the plant.

For optimum usable energy, select a bulb that has the lowest wattage with the highest usable energy coefficient.

Feminized Cannabis Seeds by Dutch Passion Seed Company, Amsterdam In November 1998 we introduced our Female Cannabis Seed. We did this after our own experiments showed that from female seed, we acquired all but 100% female offspring. In the meantime, we are six months further. We have received a lot of feedback from our customers. The reactions are mostly positive, clients who have successfully produced almost 100% female offspring. However, there have been reactions from customers who found a few hermaphrodites or male plants.

Apparently environmental influences affect the sex of the female seeds as well. Because of the fact that Female seeds do not grow into female plants under all circumstances, we changed the name from Female Cannabis Seeds into Feminized Cannabis Seeds. From literature and from our own findings it appears that the growth of a male or a female plant from seed, except for the predisposition in the gender chromosomes, also depends on various environmental factors. Not only the origination of entirely male or female plants is partly affected by these environmental factors, but the number of male and female flowers on a hermaphrodite plant is also affected as well.

The environmental factors that influence the sex of the plant (or the flower in the case of hermaphrodites), are among other things:

1) the quantity of nitrogen and potassium of the seedbed,

2) humidity and moistness of the seedbed,

3) level of temperatures,

 4) color of the light used,

5) length of daylight.

Stress, any form of stress, makes that more male individuals will originate from seed. Even the taking of cuttings from female plants may produce male or hermaphrodite cuttings.

To optimize the result, changes in one or more of the above-mentioned environmental factors for a certain period during growth may be applied. During this time these environmental factors will deviate from the standard growing system for maximum harvest and quality, as described in nursery literature.

The desired changes) in the environmental factors are started from the moment that the seedling has three pairs of real leaves (not counting the seed-lobes). This is the moment that male and/or female predisposition inflorescence is being formed. After approximately two weeks the standard growing system can be reconverted to FEMINIZED CANNABIS SEEDS by Dutch Passion Seed Company, Amsterdam (continued) Of the 5 above-mentioned environmental factors the first three are the most practical: 1) Level of nitrogen and potassium of the seed bed. A heightening of the standard level of nitrogen makes for more female plants originating from the seeds. A lowering of the nitrogen level shows more male plants. A heightening of the level of potassium tends to show more male plants, while a lowering of the potassium level shows more female plants. A combination of a higher nitrogen level for the period of a week or two and a lowering of the potassium level is recommended. 2) Humidity and moistness of the seedbed. Higher humidity makes for an increase in the number of female plants from seed, a lowering for an increase in male plants. The same is valid for the moistness of the seedbed. 3) Level of temperatures. Lower temperatures make for a larger number of female plants, higher temperatures for more male plants. 4) Color of light: More blue light makes for female plants from seed, more red light makes for more male plants. 5) Hours of daylight. Few hours of daylight (for example 14 hours) makes for more female individuals, a long day (for example 18 hours) makes for more male plants.


Insects, fungus, bacteria and more

Treat with NO-DAMP or other mild fungicides. Be sure roots are already wet before root-drench treatment: NO-DAMP contains alcohol that could damage dry roots or unrooted cuttings. Treat plants once a week until plants recover.
VIGOROUS PLANTS – GREEN GROWTH (no flowers or crop on the plant) Spray top-growth well with SAFER’S GARDEN FUNGICIDE
Wet all leaves until liquid runs off leaves.

– you will definitely BURN your crop! Treat your plants once a week
– best time to spray is late in the day, so the plants can dry in the dark; avoid spraying in strong light.


Treat plants by hand-watering BENOMYL fungicide into the roots.
Water enough BENOMYL solution into the roots to DRENCH the entire root system. Treat the plants when the roots are ALREADY WET from feeding or watering and when they won’t be watered again for at least a few hours. Treat once a week.


Avoid high temperature and strong fertilizers until plants recover. The disease can become tolerant of a fungicide if used many times” after you have used one product 3 or 4 times in a row, switch to another suitable product, and attack the disease with a new weapon.



Spider Mites
Look for browning of foliage, sometimes accompanied by extensive webbing. Mite damage occurs most often during hot, dry weather in July and August. Look for very small, spider-like creatures that are almost invisible without magnification.

Use a hand lens of at least 10X magnification to examine undersides of leaves for the presence of mites Fungus Gnats
These flies are gray or black, delicate, and about 3 to 6 mm long. The young are white maggots with blackheads, found in decaying plant matter. They thrive in moist soil. The adults are a harmless nuisance, but the maggots can injure the roots. Affected plants appear stunted, and foliage may drop.

These small delicate, white insects suck the plant juices and are usually found on the underside of leaves or fluttering about the plant. Leaf surfaces are covered with sticky honeydew excreted by these insects. Leaves become pale or discolored.

Several species of thrips may infest house plants. Thrips are small, slender pests, the young being whitish to yellow or orange and the adults brown or black. Adults are hard to see because they fly about the plant, especially when disturbed. They feed by rasping the plant tissue and sucking the juice, causing a silvery, speckled appearance to leaf surfaces. Dots of black excrements cover a badly infested plant and small scars are formed where each female placed eggs in the plant tissue.


Fungus Gnats

This question deals with a successful grower who’s created a productive garden with good growing conditions, so many potential causes of the problem (overheating, crowding, mites) can be eliminated. He’s already had these problems and corrected them! Even experienced gardeners can be puzzled by fungus gnat symptoms. The larvae of these pests can destroy a garden, working out of sight as they chew the plant roots and drain the sap. Even the adults – tiny flies that hang around the bottom of the plant and run across the surface of the grow medium look harmless. Usually, growers only see a few tiny flies, and sometimes the flies lay their eggs near the plant’s roots and escape unnoticed by the gardener.

This hidden activity by fungus gnat larvae separates gnats from top growth -attacking insects like thrips or spider mites. Even careful examination of the root zone may miss these tiny larvae – the grower would see only damaged and discolored roots. Meanwhile, the baby bugs are: Chewing and damaging root tissue, interfering with nutrient and water uptake. Sucking sap from roots that were necessary for the needs of the plant. -Infecting the damaged roots with fungus disease. This last activity is the reason these insects got their name – they carry disease spores on their bodies that can infect the damaged roots easily, creating more problems for the grower. New fungus gnat problems in a garden usually occur in autumn (as cooler weather forces insects indoors) or spring (when over-wintering eggs outdoors hatch and the flies find their way into the grow room).

Continuing fungus gnat problems can happen any time of the year, indicating that an infected plant somewhere in the garden or nearby (house plants, or outdoors near the indoor garden) is serving as a continual source of these pests. Often the problem is traced to stock plants, which are usually neglected, old, and root-bound. And good riddance! Because of the severe damage, these pests can inflict on a garden, store staff and growers must be aware of how to identify and handle them. Bright yellow leaves – normally shaped, no wrinkles or spots – and very slow growth are strong clues to their presence in the garden. Have growers search for “tiny flies – like fruit flies” hovering near the base of the plant or on the grow medium. Once spotted, urge immediate treatment of all plants, not just the ones that look sick – the larvae can already be present and start to damage plants that still look healthy, and untreated larvae turn into more flies to re-infect the garden.

Plants recovering from fungus gnat problems still face the risk of disease problems – remember that these bugs can spread fungus spores to damaged roots. As a precaution, these plants should be given a treatment with a fungicide a day or two after pesticide application. A root drench is more effective than spraying the top growth. Follow a similar procedure to your use of pesticides, drenching the entire root zone with fungicide solution, with irrigation pumps off for at least several hours. Left t over fungicide in the root zone will not interfere with nutrients, so it’s not necessary to drain and replace the fertilizer mix.

Yellow sticky cards are very useful as an early warning system for these flying pests, since the gnats are often attracted to the bright yellow surface. Soon, new gangs of these bugs will be pulling “home invasions” on our gardeners as the milder weather will allow gnat eggs to hatch out of doors. Fortunately, treating this pest is very straight forward: Wilson’s Potting Soil Insecticide or Wilson’s Fungus Gnat Powder will eliminate fungus gnats from the root zone, usually with a single application of pesticide.

These products are very gentle on the plant, making them useful for all grow mediums. We do not recommend stronger, outdoor pesticides (liquid diazinon 5% strength) since these can cause major damage or death to an indoor garden! Stick with safe, effective products that allow plants to recover quickly. Using these products with “Potting Soil” plants is very simple: just sprinkle the powder on to the soil and water it in.


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