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Exploring the benefits of compost teas for gardening

Teas can be particularly useful when large amounts of organic matter are not available, which is the case for a lot of gardeners.

About 20 years ago, I took a harrowing night ride down to the Coast in the middle of winter with my two fellow gardening friends.

To take our minds off the tension and terror of that trip, we kicked around the idea of starting a business selling manure teas in little tea bags. Some of the crazy names we came up with were Turkey Turd Tea, Llama Bean Tea, Chickpee Tea, Barn Apple Tea, Moo-Poo Tea, Donkey Dung Tea and a Blue Chip Special Blend –  just to name a few. We were giggling and laughing so much, those six hours of blinding blizzard blessedly passed quickly, and we still have a good tea-hee about it to this day.

But in hindsight, maybe we should have poured our time into the “Tea Time with Turds” biz, because using the extracts of excrement, as well as compost, plant and other teas, is all part of the green garden movement, which is shifting away from chemical fertilizers, toxic herbicides and pesticides, and digging into nature’s powerful toolbox.

These loaded liquids, used both on soils and as foliar sprays, help to: revitalize damaged and dead soils by increasing good microbial populations to break down organic matter; potentially add biodiversity to your soil; can act as natural inoculants to suppress disease; can be excellent for more nutrient-based foods by cheaply increasing the quality, yield and health of plants and soil; allows nutrients to become more readily available to plants through the soil, stems and leaves; is inexpensive and simple to make; spreads farther than compost; is great for shoulder and growing seasons; can’t be overused and plays an essential role in the transition to organic practices.

Teas can be particularly useful when large amounts of organic matter are not available, which is the case for a lot of gardeners.  (See International Compost Tea Council for more info.)

What’s important to remember and understand is that each field, garden and natural ecosystem is unique with respect to microclimate, soil, biological diversity, amounts of organic matter, water conditions, etc. and our goal as gardeners and farmers is always to support ecosystem processes and health. Most living organisms are able to produce most of the vitamins they require in a healthy, biologically diverse soil ecosystem. Increasing the biological activity in the soil is our number one priority by maintaining a diverse amount of nutrients to feed the soil food web and let nature do it’s thing, rather than us trying to figure out what it needs and doesn’t need.  Remember, just because something is “organic,” doesn’t mean it’s harmless. Ecosystem balance is always key and, just like in our bodies, too much of one thing can be detrimental – even toxic – rather than beneficial.

Microbial extracts (or leachates), teas and brews can be loosely divided into two main groups:  a) compost, soil, and plant extracts and b) specific microbial cultures. “Compost tea” is a loosely-used term and is applied to many different kinds of brews.  (Note:  Mycorrhizal fungi cannot be propagated in compost teas, as they are symbiotic – or buddy system – organisms that can only live in association with plant roots).   Many plant extracts contain powerful organic or chemical substances, which have been used by mankind in the preparation of food, medicine, pest control, bio-stimulants, liquid fertilizers and a source of plant hormones.

When making any kind of these teas, use water from rain, ponds or streams if you can, because household water from a municipal source has chlorine in it which, of course, kills microbes. If not easily available, fill your bucket and leave the water to sit overnight to let the chemical off-gas or aerating it for approximately 30 minutes.  (You should do that with your drinking water too, so it doesn’t kill the beneficial microbes in your gut.)

Compost and other plant teas are usually fed to the roots of your plants, so simply water into the soil.  Foliar feeding can also be done and the helpful microbes and bacteria in the tea aid in fighting off viruses, fungi, pests and diseases. Teas can be used as frequently as you wish, but it’s especially effective in the shoulder seasons. The best time of the day to apply the tea is in the early morning and evening to avoid the killer UV rays, rapid evaporation or chance of burning the leaves. Also, keep your garden properly watered so the microbes, like all living things, can stay alive to do their important jobs.

Unfortunately, there’s never enough space to really get into the nitty-gritty of things, so this topic will be stretched into two columns in order to cover as much ground as I can.