Compost Tea

August 1, 2017

Every organic gardener knows compost. Grass clippings, spent stems and stalks, shredded leaves, kitchen scraps all placed in a pile (or a composter) with the correct amount of moisture and ultimately, you have compost. There is nothing better for your garden. As a fertilizer, soil amendment or mulch, plants love it.

In the early days of organic gardening, compost tea consisted of putting some manure into a bucket of water, letting it steep and then feeding to various plants. This concoction was actually “manure tea” and is no longer recommended due to possible contamination by a variety of pathogenic organisms.

Today, compost tea is an aerated solution that has taken the beneficial microorganisms from compost and combined them with other nutrients. It is a concentrated liquid created by a process that uses a pump to inject air through a compost solution to increase the numbers of beneficial organisms as an organic approach to plant and soil care. It requires a “brewer”, which provides the ideal conditions for the microbes and organisms in the compost “food” to multiply, thereby providing plants with a highly concentrated organic solution. This solution can then be sprayed on your plants and soil for a variety of positive and beneficial advantages.

Compost tea, when properly mixed and aerated increases the number of beneficial bacteria and other microbes which results in healthier plants. It helps extend root systems. It increases water and nutrient retention. The microorganisms assist in the breakdown of toxins in the soil and on the plants. It cannot be over applied as it is completely natural. It reduces the use of chemical pesticides, herbicides and fertilizer as the amount of organisms compete with disease-causing organisms.

Be advised that compost tea is not a “silver bullet” for all of the problems in your garden. One needs to continue other practices such as organic fertilizing, soil amending, cover crops, adding compost itself, proper irrigation and mulching.

New technology of adding air in water to compost with food to make compost tea and using it to suppress diseases is now about 15 years old. Dr. Elaine Ingham, Soil Microbiologist and founder of Soil Foodweb, Inc. reports that through repeated field trials on agricultural crops, the compost tea does, in fact, create an amazing combination of fungi, bacteria, protozoa and beneficial nematodes to benefit plants.

Dr. Ingham uses compost tea in her own garden every spring and recommends using it at least once a month on not so healthy or un-established organic gardens.

Unfortunately, there are few scientific studies available to confirm the benefits of compost tea. Also, compost tea varies due to the actual materials used to make it and the particular microbes present in the solution. Many gardeners say it doesn’t really work at all and that providing compost itself (without the “tea”) is all that is needed.

The University of Connecticut’s Soil Nutrient Analysis Laboratory states that “Although the art and science of using actively aerated compost tea (AACT) is still in its infancy, it may be well worth your time to investigate the use of compost tea in your yard. It may not solve all your disease problems but it seems likely to encourage overall plant health.”

If you would like to try brewing compost tea, I would recommend a company called “Keep It Simple, Inc.” It provides the equipment and additives that I use in my own garden throughout the season. Jeff Lowenfels, author of “Teaming With Microbes, A Gardener’s Guide to the Soil Food Web” also uses the equipment himself in Alaska.

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