Compost Tea

Compost tea is a helpful way to fertilize your garden. Compost tea is reported to increase disease resistance in plants, reduce fertilizer and water needs as well as plant stress, and improve soil structure, aeration,
retention of nutrients, and cycling of nutrients into plant-available forms. Compost tea puts the microbes back into soils that have been subjected to chemicals or soils that are naturally limited in microbial activity. When applied to plant foliage, compost tea prevents harmful substances, including disease organisms, from reaching the plant. It also increases the amount of nutrients taken up by foliar-applied fertilizers.

What is Compost Tea?

Compost tea is an aerobically brewed liquid extract made from compost. Compost tea can contains tons of beneficial organisms, including bacteria, protozoa, and nematodes, as well as nutrients that are essential for plant and soil health.

How is Compost Tea Made?

On the simplest level, making compost tea requires a container, water, and compost. You can actually buy a home gardener compost tea brewing system, which usually make 5 gallons at a time, can be purchased for about $65 to $150.

To make compost tea, do your very best to get non-chlorinated water. (Chlorine is designed to KILL things, remember?) Even letting an open container sit out overnight will help reduce chlorine concentration.

How is Compost Tea Applied?

You can spray compost tea on leaves, branches, and trunks of plants. Just pour it into the soil around the base of the plant. You can use it as a root dip for bare-root plants, transplants, and cuttings. The frequency of application depends upon the use. For foliar application of actively growing plants, such as flowers or vegetables, compost tea can be sprayed on the foliage as frequently as weekly, especially if you’re trying to combat diseases… a healthy plant is a stronger plant! 🙂

When you first begin to improve your soil, it will benefit from applications of compost tea four to five times during the growing season. Once your soil is in good health, three yearly applications — in spring, summer, and fall — are usually adequate.

Do I Still Need to Use Compost or Fertilizer?

Compost tea is like the fourth leg of a stool, the other legs being organic matter, additional nutrients, and mycorrhizae. Straight up compost is still the first choice for adding organic matter to the soil. Kelp and fish emulsion, as well as other organic fertilizers, are your best choices for adding nutrients. Mycorrhizae inoculants are the other helpful additions used to fertilize your organic garden. They are a symbiotic fungal mixture that attaches to the plant roots and helps to feed and protect the plant. And that link to the little half pound jar will treat 70 gallons of water. Not bad considering you simply have to “innoculate”.

Adding one more thing to do in the garden may seem like one too many, but the reports on the success of using compost tea as part of a unified system of organic growing methods are difficult to ignore. The possibility of healthier, more productive plants is an irresistible siren call.

Dr. Elaine Ingham, the soil biologist who has played one of the biggest roles in the evolution of compost tea, has published the fifth edition of The Compost Tea Brewing Manual. This comprehensive manual on making, applying, and assessing compost tea
includes up-to-date information on methods, research, and practical examples.

The International Compost Tea Council Web site provides answers to the most frequently asked questions about making and using compost tea. You’ll also find a selection of recommended reading on microbiology, natural gardening, soils, agriculture, and the environment.

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