Organic gardening is really microbial gardening. For a plant to uptake any element, it must be broken down so the plant can absorb it. In soil gardening, we rely on the millions of microbes living around a plant’s rhizosphere to break organic matter down into absorbable elements. Sometimes a microbe itself breaks matter down and sometimes a by-product of a microbe is responsible. In conventional hydroponics, chemical fertilizers are used that have already been broken down in a laboratory and are ready to be absorbed by the plant’s roots. Conventional hydroponic gardening bypasses the microbial field almost completely. So how can we continue taking advantage of the speed and production of hydroponic gardens if we want to grow organically? The answer lies in brewing microbial rich teas and nutrient solutions.
By brewing microbial teas, an organic hydro-gardener can jump start the process of breaking down organic matter. Water, oxygen, raw organic source (bat guano, sea bird guano, earthworm castings, kelp meal, etc.) and time are the ingredients necessary to brew a microbial rich nutrient solution. It will help to add a source of carbohydrates to help feed the microbial population. It also can be beneficial to add enzyme formulas or mycorrhizae products directly to the brewing process. Take your raw organic source (I use worm casting because of its diverse nutrient content and high microbial population) and place inside of a filter bag. Fill a sterilized container (i.e. a five gallon bucket) with distilled water or reverse osmosis water. Chlorinated tap water will kill many of the beneficial microbes and should be avoided. Place the filter bag in the water. Using a small aquarium pump and an air stone, deliver air to the water continuously for 24 hours. When removing the filter bag squeeze it lightly (much like a tea bag after steeping). Then stir the solution to make it uniform. It is now ready to be diluted for feeding. Experimentation with dilution rates will be necessary, but a good starting point for direct root feeding is a half cup solution per gallon of water. For foliar feeding, a quarter cup per gallon of water is a good starting point.
Over time you will develop your own tea brewing methods that can enhance your medical marijuana’s growth, flavor and potency. I have found a perpetual brewing process to be the most effective. As soon as I am done brewing a batch I start another so my precious plants are alway receiving a abundant dose of fresh microbes. If brewing isn’t your cup of tea (pun intended) don’t worry, many fertilizer companies are producing organic nutrient solutions and teas for hydro-gardening.