Expert tips on growing cannabis from The Ones That Know Best. Everything you always wanted to know about growing but you had noone to ask..

CANNABIS GROWING INTRODUCTION

This page contains loads of info on growing cannabis in an indoor garden. Just read, pick a room and get going! Ofcourse we need to tell you that this activity might be illegal in your country/state. We strongly advise against illegally growing cannabis. But if it's okay to do over there, hey, here's all you need to know:

For the small grower, or new starter we believe that the easiest and cheapest method is to use soil. For example: organic pre fertlised soil is very easy to use because it needs no feed just water and possibly a small pH. adjustment to be between 6.2 and 5.5 which can be measured with any cheap pH. testing kit or meter. (If the pot sizes are small and the plants are left to get big, additional fertiliser will be needed in the cannabis plants later stages of life.)

With hydroponics there are many varieties of media to choose from i.e.: Rockwall, clay pebbles, coconut fibre, prelate etc.

Also there are different methods for the iragation of these media such as Flood and Drain, Libra tray's and drippers, pots and drippers. (Both the latter can be either "To Waste" or "Recirculated", depending on the type of medium used). There are also systems that use no media just oxygenated water and nutrient travelling across the roots. The two most commonly known are the N.F.T. systems (nutrient film technique) and Aeroflow systems. Both achieve amazing results.

LIGHTING THE PLANTS

There are two major types of lighting that you can use, primarily white and yellow, although the High Discharge Lamps are also divided into two types. These are Plantas which favour the Blue end of the spectrum and H.P.S. Nav - T / Son - T which are outputting at the Red end of the spectrum. White light is beneficial to healthy growth; yellow light is essential for flowering stage. Fluorescent tubes or Metal Halide lamps can be used as a source of white light and for the yellow light we have an extensive range of High Pressure Sodium lamps; these vary in strength from 250 to 1000 Watts. The plants light needs are:

18 hours of light per 24 hours in the growing phase.

12 hours of light per 24 hours in the flowering phase.

The most efficient lamp for output (light output and energy use) is the 600 Watt lamp. The 1000 Watt lamp is avoided as it produces excessive amounts of heat per light output. The 400 Watt lamp can be useful if there is a limited height within the workplace, as it can be hung closer to the plants. The minimum distance between the lamps and the plant (to prevent burning) are:

250 Watt: minimum 20 cm

400 Watt: minimum 35 cm

600 Watt: minimum 45 cm

1000 Watt: minimum 90 cm

They're two different types of lamps to choose from. The first type is where the reflector and bulb are separate from the heavy ballast. The indoor grower tends to favour these lamps for ease of placement. The second type is where the ballast is connected to the bulb and reflector which are generally cheaper, but quite heavy so more suited to commercial and industrial locations.

When using several lamps at once it is essential that they can be turned on and off safely. It is essential to use good switches, preferrably those that conform to European safety standards.

Light intensity in Lumen (Lux per M2)	Surfaces that can effectively be lit
For a 400-Watt bulb it is 48000 Lumen	0,7 M2
For a 600-Watt bulb it is 98000 Lumen	1.2 M2
For a 1000-Watt bulb it is 115000 Lumen	1,7 M2

CLIMATE CONTROL

Choosing the correct ventilation system sometimes can be quite complex. It is very important that you have the right system for the area that you have chosen for your indoor garden.

Choosing a ventilation system requires bearing in mind the following factors:

The temperature of the space, the difference between a cellar and an attic.

Air supplies and discharge possibilities: the channel sizes and the temperature of the supply air.

The sensitivity of surrounding areas to noise and odour.

The number of lamps and other sources of heat.

We use 2 types of discharge ventilators: snailhouse ventilators and tube ventilators. The snail is quieter, the tube is stronger.

Air discharge is not only important for temperature control as well as the supply of fresh air. Fresh means in our case richer in CO², carbon dioxide. From CO² and water under influence of light, sugars and oxygen are made: photosynthesis. In the grow-area there should always be ample CO² otherwise the plant will grow and bloom slower. For strategic refreshment between the plants we use moving ventilators, for the whole room a large discharge ventilator takes care of fresh air. In winter it can be useful to artificially add CO² because one generally discharges less air due to low temperatures.

If it is important that the smell does not travel outside the building then the use of odour filters is necessary. The most tested method is the extraction of air through carbon cylinders. This cylinder consists of two perforated metal walls, among which active carbon-grains can be found. All the air pulled through here (not too fast!) is odour free. To keep the carbon as active as possible another filter is put around (clean). Because these cylinders have a high resistance we use them mostly in combination with a tube ventilator.

The inline fan
The inline fan is very powerful, reliable, and easy to install. It's ideal for the smaller grow room to control air input and extraction (1 - 9 lights max).

The snail ventilator
The snail ventilator comes on its own, or in an acoustically insulated metal box on rubber vibration mounts these fans are extremely powerful and very quiet. The perfect extractor for the larger growroom, or for people who just don't want noise to be a problem.

Ducting
Air discharge also means air supply, for this an opening has to be made in the area or room, as close as possible to the floor and as far away from the discharge point as possible. In order to muffle the noise of extractors an acoustically insulated tube is used, this is double walled and perforated inside and is able to absorb almost all the sound.

The fan controller
The fan controller controls the extractor thermostatically but ensures that a determined minimum air stream remains, which is important for fresh air to pass between the plants. A good controller has two adjustment buttons: one for the adjustment of the minimum motor power and the other for setting the correct temperature. If you work with a thermostat alone then there is more temperature wastage due to the switching on and off. The fan controller is made to be user friendly and can easy regulate up to 1000 watt fan.

Carbon filters
Carbon filters are used in grow rooms to clean unwanted spores dust and smell particles. They are installed inside the grow room. They then are connected to the intake end of the extractor fan. When the fan engages the air is pulled through the outer pre filter and then through the carbon granules, by the time the air is through the carbon it is completely clean of any unwanted smells or particles.

Carbon dioxide (CO²) enrichment
For successful growth there should be a high level of CO² in the atmosphere of the grow room. The most accurate method is to use a CO² Controller. This constantly measures the level of CO² in the room and can as a result control 2 relays, one for the CO² injection and one for air extraction. The easiest source is a CO² bottle complete with a reduce valve and gas clip. The controller automatically opens and closes this clip electronically.

In order not to waste any CO² there are recoil clips available for the air discharge and supply vents, which closes in passive stand.

It is possible to use the CO² cannister with a gas regulator on its own (tap + pressure meter + flow meter + gas clip) but this is not as accurate as using a digital timer. The timer can be programmed appropriately for the room's contents. This can lead to an significant increase yield.

Humidity
The humidity of the air is important when rearing young plants; these lose very little moisture as vapour when young, resulting in a dry growing room at the beginning. The correct humidity (for growing small plants) is around 60% and 80% r.h. (relative humidity).

IRRIGATION

Here we name points about the underside of the plant: the roots-system. One of the first, and important choices is which medium should be used.

Soil
Cultivation in soil is generally in larger pots, this affects the amount of fertilisers that can be used. The size of the pot is dependent on the amount of plants wanted per m2. In general the rule is: the more plants per M², the smaller they are. With 35 or more plants the new cuttings will almost immediately bloom. Opinions differ, we advise an average between 9 and 25 plants per M².

Hydroponics
Libra trays are advisable for those with larger areas and wishing to cultivate more than 16 plants per M², these are used in conjunction with rock wool or Coco slabs. Simple to install and less work when planting. You can see that pots for hydroponics are generally smaller, because in the case of hydroponics absorption of fertilisers is at an optimum. Plants need less roots for the same yield.

NFT & Aeroflow
These are systems that use no media just oxygenated water and nutrient travelling across the roots. The two most commonly known are the N.F.T. systems (nutrient film technique) and Aeroflow systems.

Automatic watering
Leaving plants for a week or so is impossible, unless an automatic watering system is procured. Automatic irrigation is possible both with soil and stone wool (hydro culture). The only difference is the mixing of the different fertilisers (see chapter substrate and fertilisers).

To catch the excess water from the pots it is advisable to place the pots on a watertight tray that has a good drainage point. For this the channel bottom comes into use; this has a central drainage point and is quickly dry again through a network of channels that lead to this point. When growing by hydroculture this is especially important so that rinsing is possible.

When irrigating by say a "Header Tank", the flow is divided between a numbers of plants. The basic requirements are a reservoir, a submersible pump, and an electronic timer to control these, a water filter, a main tap and a number of plastic hoses to water the plants. On the end of these hoses also known as capillaries, is a sort of pricker, the plug (spike). A mechanical float in the barrel avoids overflowing as the barrel is filled.

It is always advisable to warm the water in the food reservoir; the ideal temperature is between 18^o C and 22^o C. Low temperature will delay or stop the plant from growing.

Irrigation with garden hose
In order to distribute the pressure one must divide after the barrel the main supply and make a circular supply. From here the complex or loose capillaries are attached. Note that the tap and water filter are positioned before the split. With this head tap you can regulate the water. The water filter removes small particles from the water and prevents blockage in the hoses.

Irrigation with PE hose
The spray plug is used in conjunction with bigger pots: with a dropper the whole surface of the pot is dampened.

SUBSTRATE/NUTRIENTS

In the previous chapter was the big choice in cultivation: soil or hydroculture. For those with a tight budget the choice is obvious: first begin with soil. When gardening with soil you must always have adequate drainage and must never have your pots sitting in old stale water, this will starve the roots at the bottom of the pot of all the oxygen they need to stay healthy. For the best results in soil always use soil fertilisers with a good name that has been well tested and sold for many years. Different liquid fertiliser are available for both vegetative growth and the flowering phase.

It is also possible to make your own organic soil mix that contains virtually all the nutrients, minerals and trace elements that we need for the healthy growth of our favorite plants. A good mix contains snail shells, fish blood, bat guano, hoof meal molasses etc… We think it stinks, but our little green friend's absolutely love the stuff. Just mix some of that organic concentrate approximately 5% with 15 % worm castings (for a little bit of nitrogen) a good quality potting compost and perlite (we recommend between 20% and 50% depending on what sort of speed you want your plants to drain. There is also a choice between a number of biological and non-biological liquid fertilisers. With hydroponics higher yields are attainable because the hydro-media contains more oxygen than earth with the same percentages of moisture. The water that plants get is at the maximum as one keeps the acidity between 5.3 and 6.0 pH. Acidity regulation and control can be done by a pH-meter. These come in different prices; begin with a simple pH meter because the special hydroculture fertilisers that are available are compounded so that they are always around 5 or 6 pH. The raising or lowering of the pH as well as the base of acidity of the food solution happens with pH- or pH+ liquids. If one can control the climate then one can control with hydroculture the root climate and these two work together for an increase in harvest.

Fertilisers For Hydroculture
Growing cubes are an outstanding media for hydroponics in pots. The pot can be directly filled from the sack; in addition the stone wool is slightly damp, preventing flying particles. Because of the small cube structure (1 cm³) it is one of the quickest substratums on which plants grow.

COCO is a product made from Coco fibres and is environmentally friendly; it comes in a slab form or in a 50 litre bag (for pots).

For the rooting and pre-growing of cuttings, rock wool is still the best solution: strong and easy to manage. They contain a lot of oxygen. Cutting blocks are available in different sizes; this has to do with the proportion of the cutting to be.

Note that you can not(!) use the kind of Rock wool that is intended for isolation in construction. These materials are made water resistant by chemicals. Get your Rock wool products intended for farming at specialised farming equipment stores.

To catch the excess water from the pots it is advisable to place the pots on a watertight tray that has a good drainage. The base of the pot has a central draining point, which is fed by a network of channels for good drainage. This is especially important in hydroculture so that water can be flushed out.

The basic requirements for irrigation are a reservoir, a plunger pump, an electronic timer to control these, a water filter, amines tap, a number of plastic hoses (capillaries) to water the plants, a tool to punch holes in the capillaries and the plug (spike).

In the winter it is advisable to warm the water in the food reservoir to a temperature of between 18^o C and 25^o C degrees.

The Coco slab is made from mechanically and thermally treated coco fibres. This treatment results in a perfectly sterile mat. The pH buffer in the cocos slab is very high this means that pH level will be stable for almost 4 weeks (idiot proof) No chemicals are used during manufacture. The slab can keep a stabile temperature. The root system thrives because of the similarity between this mat and the natural environment.

Fertilisers For Hydroculture
These fertilisers are all liquids, sold ready for use. They are composed of two components that are added to water in the reservoir, in equal amounts. The concentration ratio is mainly 1:250.

The acidity of a solution is given as pH. This scale runs from 0 (acid) to 14 (alkali). Lowering of the pH (acidity) can be done with two sorts of acid; normally saltpetre is used during growth and phosphor during flowering. This is because one acid bonds with Nitrogen and the other with phosphor. An important property of the nutrition applied to the hydroculture is the strength of the solution. The strength is determined by the level of salts in the solution, which is measured in EC. The optimum strength is between 1 and 3 EC (or 10 and 30 depending on scale).

PEST CONTROL

The most common infestation in indoor gardening is the red spider mite. Their presence is recognisable by small, light coloured suck marks on the top of the leaf; these look like small white dots. In an advanced stage they form small spiderwebs. Spider mites thrive in a dry, warm environment. If you catch the mite in its very early stages, natural predators can be used such as the Roof mite. The Roof mite has to be introduced into the environment early to be effective. It is advisable to always have the Roof mite in your garden. There is also a biological spray called Hurricane, which can be used if you have a large infestation, and the Roof mite prove ineffective.

When it is in later stages the infestation can only be treated chemically. These are two options:

Spider killer, which does not harm the Roof mite, but does not kill the eggs.

Disinfectant, which is extremely effective at eliminating all insects and eggs.

One of the other main pests associated with indoor cultivation is the Root Louse and the larvae of the Root fly, which attack the root hairs. This occurs mostly with Rock wool cubes and clay pebbles and it is recommended that you inspect the roots quite often. The root louse is between 0.5 and 2mm long. The only way to prevent the root louse is to eliminate all flies from the grow room by the use of fly paper, air filtration of incoming air, regular spraying with a mild biological pesticide and the introduction of natural predators into the grow room environment (with predator cards). If you do get infested then you put Root louse killer in the plant's water.

If the infestation has well and truly begun then there only one thing left to do. Blast them with chemical insecticide. There are many of these products out there and are subject to change. Allways check the labels and follow the instructions on harvestable produce, since someone will eventually consume the cannabis. Try not to use chemicals in the last stages of flowering.

With the predator chart all kinds of natural enemies can be ordered at specialsied stores and websites. When you have had an infestation, you must always sterilise the grow room with either a strong solution of bleach or insecticide to make sure there are no eggs still left alive and dormant in the grow room waiting for the next lot of plants to be introduced to the room. Keep it clean.

To prevent any contamination with insects, allways make sure you have none on your clothes before entering your indoor garden. After a visit to the garden or engaging in outdoor activity change your clotches and shoes when tending to your plants. Never let furry pets in to the room. They may have tiny hitchhikers on them. And most importantly, try to keep other growers away, since they might have problems you don't want.

Some extra pointers

Heavy plants
As the cannabis plant begins the last two weeks of flowering, it often falls all over the place because of the weight of the fruits. This can be prevented in a number of ways. The stretching of lines or even so called jojo's (Nicorol) could be attached, an elastic thread that rolls itself up as the plants grow.