When the decision was made to grow organic, a lot of research went into finding out how we were going to be able to improve the physical, chemical and biological properties of our soil to grow healthy plants without the use of traditional or conventional soil amendments. It required a shift in strategy from feeding a plant in a basically lifeless soil, to using a soil full of life and feeding the soil, which in turn will feed the plant. How would we be able to get these vital nutrients and organisms into our soil? This 100 gallon liquid compost tea brewer seemed to be the best answer.
Compost is organic matter that has been broken down into a simpler form so that its essential nutrients are more readily available to the plants, and it’s full of beneficial microbes. The brewing process extracts these compounds and microbes into the liquid so that it can be easily applied to the plants. Brewing also also provides an environment in which all those microbes can rapidly multiply. Once applied, these microbes go to work in the soil breaking down and releasing all kinds of nutrients and other compounds the plants love. All of this combines with the compost already present in our soil mix providing a source of slow release nutrients and improving water retention. All of these beneficial microbes also work to overwhelm and crowd out disease organisms.
To begin the brewing process, we fill the tank with collected rainwater. Using rainwater is beneficial to our plants since it does not contain chlorine, has fewer impurities, a neutral pH, it’s free and the plants love it! Next we turn on the diffusers inside the brewing tank. This allows the rainwater to aerate and offers it a chance to warm up a bit before we start adding the compost. While we are waiting, we fill the mesh-lined baskets with the dark, rich compost. It looks and feels a lot like loose leaf tea. Once the water is warmed, we add a catalyst (a food resource for the microbes) that helps begin the process. Next, we place the compost filled baskets into their respective slots. As the water begins to combine with the compost, the diffusers on the ends of each hose begin percolating the tea allowing the microbes to begin reproducing. It takes a full 24 hours for the tea to brew and fully release its microorganisms into the liquid. Sometimes the tea foams up and over the basket edge. To reduce the chance of foaming we add organic sunflower oil. In order to take full advantage of the microbial life now residing in the tea, we apply it to our plants with a dedicated portable spray unit. We also run it through a series of injectors to dilute the tea proportionally into our in-house watering system where we are then able to use our automatic watering booms to water large areas of plants. Additionally, we often add environmentally beneficial nematodes to the compost mixture before spraying. These nematodes are microscopic entities that aggressively seek out, enter and control the larva of fungus gnats and Sciarids, along with the Western Flower Thrip – the number one pest in the greenhouse.
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