How to Farm With Compost Tea

Farm soil can be amended with compost tea applied at the right amounts.

Compost tea is made by adding compost to water and letting it age for a few days so microbes beneficial to plant growth will increase in number. Air is often pumped into the mixture during the process to help the organisms flourish. When the beneficial microbe count is at the right level, the compost tea is applied to soil to help plants fight disease and remain healthy. Compost tea can be made in small amounts for small gardens or in large quantities if you are farming with compost tea. A large farm setting, however, involves following regulations and testing requirements.

Things You'll Need

• Compost tea
• Application device

Instructions

1. Make compost tea based on National Organic Program standards to ensure no harmful levels of fecal bacteria are in the compost tea. Fecal bacteria from raw manure makes people sick if contaminated produce is consumed. Therefore, manure compost must be composted at high temperatures to kill harmful bacteria before it is used to make compost tea and applied to food crops. Then the compost tea must be tested for harmful bacteria by a professional lab before being applied to food crops. Compost tea not made from manure can be applied without restriction.

2. Test the soil in the area where the compost tea is to be applied as well as the compost tea by contacting your local County Agricultural Extension Office and asking for assistance. This is how you find out what nutrients are lacking in the soil and how much compost tea to apply. Compost tea contains phosphorous, which builds up in the soil to toxic levels that interfere with organic certification and adversely affect plant growth.

3. Drench the soil with the compost tea and use as a foliar spray over the target plants at the rate recommended by your soil and compost tea test. If the compost tea was made from manure, it must be applied more than 90 days before harvesting crops with fruit that stays above the ground, and 120 days before harvesting crops that touch the ground.

References

• National Sustainable Agriculture Information Service: Methods of Compost Tea Production
• Maine Organic Farmers and Gardeners Association:An Update on Compost Tea: Benefits, Risks, Regulation
• Extension: Making and Using Compost for Organic Farming
• The Rodale Institute: Compost Tea Production, Application and Benefits

Resources

• USDA: Welcome to the National Organic Program
• USDA: Cooperative Extension System Offices