Hydroponic Growing Systems
There are a variety of hydroponic systems for you to choose from. Each has its own advantages and which one you choose is down to personal preference.
Most hydroponic shops will offer complete kits with good advice. If your budget stretches to this then they are ideal. However you will ultimately end up buying equipment that you don’t really need. It is relatively easy to construct your own systems following the basic principles.- The art of growing marijuana with the roots dangling inside a light and water tight box and small emitters producing a fine mist on a regular basis. The mist creates a humid but aerated environment with nutrients.
Aeroponics - The art of growing marijuana with the roots dangling inside a light and water tight box and small emitters producing a fine mist on a regular basis. The mist creates a humid but aerated environment with nutrients.
Continuous Flow / Top Feed System – A great hydroponic system that produces a ‘continuous feed’ of nutrients into the top of the grow medium. It is also quite similar to the Ebb and Flow system and the NFT system.
Deep water Culture (DWC) / Recirculating Direct Water Culture (RDWC) / Bubbleponics hydroponic system – This concept is different to most, whereby the roots system is actually swimming in the nutrients solution. To help provide adequate oxygen an aeration stone, similar to one use in aquariums is used to blast air around the roots. This can all be done over a plastic water tight drum.
Drip irrigation hydroponics - Another totally different hydroponic system to grow marijuana. Small emitters drip feed your marijuana plants from the top, near the trunk. The nutrient solution drips down into the medium and feeds the plans. Very water efficient, low evaporation issues too.
Ebb and Flow hydroponics – A basic but functional system with your pots situated in a tray above the reservoir. The reservoir pumps the nutrient solution up and into the pan which ‘flows’ past the pots and in turn feeds them. The nutrients solution is then allowed to ‘ebb’ away back into the reservoir.
Nutrient Film Technique (NFT) – More efficient than most and keeps aeration of the plants roots in order. Your plants are held in aggregate above a slightly tilted tray, with a thin film of nutrients flowing from top to bottom past the roots of your marijuana.
Wick System – A really basic system that is great for a couple of plants or if you are just starting out as there is no need for pumps, timers or aeration systems. Simply connect your pots with thick ‘wick’ dipped into the reservoir and capillary action will do the rest!
Sea of Green – A Dutch growing method which produces a Sea of Green heads (kolas), we love it.
Screen of Green – This is a Dutch growing method similar to Sea of Green, exciting stuff if you want to go more hard core.
Continuous Flow / Top Feed Grow Systems
Top feed systems use an emitter to feed each individual plant at its base. These emitters are attached to a single, multi-valve unit which in turn is pump-fed from the reservoir. Any run-off from the plants is fed back into the reservoir via a drainage hole. Top feed systems will require some adjusting to get the quantities right, but as with the ebb and flow system above, 15 minutes feed 3 to 4 times a day is a good starting point.
Ebb and Flow Grow Systems
These low maintenance systems are ideal for growing in Rockwool and are the system of choice for many amateur growers. Plants are placed in their pots, in a tray that can hold up to around 6” (15cm) of nutrient solution. A timed pump periodically floods the base of the tray from a reservoir, start with 4 times per day for as long as it takes to pump enough solution the base of the plant stem. When the pump switches off, the solution drains back down the same tube with the remainder staying behind in the medium which the plants then utilize. To avoid flooding, an overflow pipe is fitted in the tray at the required level (just lower than the base of the plant stem) which feeds solution back into the reservoir. Remember to always keep your growing area higher than the reservoir. This way, when pumps are off or they are accidentally left on the solution will still drain back down into the reservoir and you should eliminate the chance of flooding.
Timings for watering vary according to the size and strain of your plants. A good starting point would be to flood the growing tray for 15 minutes, 3 to 4 times during the plant’s daylight cycle.
Wick Grow Systems
A wick system works passively. That is to say that there are no pumps needed to move the water but usually one to keep the solution aerated. The nutrient solution is pulled up to the plant via a wick (you can use thick acrylic cord) by the force of capillary action. This way the plant will take only the amount of liquid that it needs. Simply have the top end of the wick buried in the plant’s growing medium and the bottom end hanging in a reservoir of your nutrient solution. Wick grow systems are ideal for beginners as there is no way to overwater the plants and no chance of leaks or floods as the main reservoir sits below the plants.
Nutrient solution reservoirs should be as large as possible. These are the vessels that hold the water and nutrients which are usually pumped through to your plants. Really you should consider having a reservoir that can supply at least one if not two weeks of nutrients. Plants inhale the nutrients and you will also get some evaporation if you don’t have a lid. Think about where you will locate the reservoir? The reservoir should be located as close to a source of water as possible, like the garden hose or if you are carrying buckets of water to it then it should be easily accessible like at the front of the room. Often growers have another reservoir or standing area for water as water straight from the faucet can have the wrong pH level while water that has been left to stand over night will often let chlorine dissipate.
Use a sturdy, clean plastic container fitted with a lid to prevent evaporation. Top up with clean water when necessary and completely change the solution and clean the reservoir once per week. You must consider the temperature learn about reverse osmosis and pH.
The best way to insulate a reservoir is to raise it off the ground with brick or polythene so air can flow under it. You could also consider wrapping the sides of the reservoir using Styrofoam, foam rubber or even newspaper.
Essential pieces of hydroponic kit
Hydroponic nutrients for vegetative and marijuana flowering stages, a meter for measuring pH, and a meter for measuring EC. An EC meter will tell you the concentration of your nutrient solution and most commercially available solutions will require you to check this.