How To Make Compost Tea

Compost tea is an effective, low-strength, natural fertilizer for seedlings and garden plants.

February 5, 2018
making compost tea

Compost tea is an effective, low-strength, natural fertilizer for seedlings and garden plants. It can suppress fungal plant diseases. The tea-brewing process extracts (and in some cases grows and multiplies) nutrients and beneficial bacteria and fungi and suspends them in water in a form that makes them quickly available to plants. 

Making compost tea doesn't require special equipment. Just follow these easy instructions:


1. Place equal parts compost and water (10 pounds mature compost for each 10 gallons of water) in a 40-gallon barrel. Protect the barrel from cold and heat.

2. Stir with a stick daily for a minimum of 5 days.

3. Strain the liquid from the compost using a cheesecloth or burlap. There should be no bubbling or off odors. Use it immediately, without further dilution.

Related: 7 Solutions To Your Most Common Compost Problems

When you brew compost tea, be sure to use mature, sweet, earthy-smelling compost. If your compost smells unpleasant, it could be anaerobic, and few beneficial microbes survive in this environment. One way to achieve tea-worthy compost is to sustain pile temperatures between 135 and 155 degrees for a week or more by turning the pile often. A well-built pile that has composted for at least a year will also produce tea-ready compost even if it did not heat up to the ideal temperature range. (Check out our composting center for more tips for making healthy compost.) 

Keep in mind that E. coli can be present in the raw ingredients of a compost pile. Minimize the risk by maintaining a hot compost pile or allowing it to fully mature. And most importantly: Don't apply compost tea to any vegetable within three weeks of harvest.