What is Compost Tea?

Compost tea is a solution made by extracting compost into a liquid form. Solid compost material is steeped or soaked in water resulting in a nutrient rich fertilizer that can be applied directly to plant foliage and soil. It is often used as a natural replacement for chemical fertilizers, fungicides, and pesticides.

The tea is typically sprayed on to non-edible plant parts to prevent disease or used as a soil-drench to improve root systems. When applied to foliage, the tea may deactivate rapidly in the sunlight. When it is introduced to the soil around a plant, microbes present in the tea will colonize debris and increase the rate of decay.

There are numerous types of compost tea, depending upon the ingredients and method of preparation used. Anaerobic compost tea is made by combining finished compost to water and allowing the mixture to steep for up to 14 days. The mixture is stirred regularly to loosen settling microbes and encourage them to transfer to the water itself.

Aerobic compost tea (ACT) is made with the assistance of air pumps or blowers. These devices aerate the tea while it is brewing. One part of high quality compost is added to 50-100 parts water. In order to be considered an aerobic tea, the water must have a dissolved oxygen content of six parts per million (PPM) or higher.

Compost tea, when used properly, enhances the taste of fruits and vegetables. It increases the brix level, or sugar to water ratio of plants. This results in smoother, sweeter tastes being noticeably present in plants that have been treated with the tea.

Another benefit of compost teas is that they cannot be overapplied. Unlike chemical fertilizers that can kill plants if used too frequently or in too great a concentration, compost teas can be applied liberally. They are made from natural materials and as such, can not harm plants or soil.

There many different compost tea kits available on the market today. These kits assist a novice tea maker in creating anywhere from five to 1,000 gallons of solution. These kits can be expensive and usually require the use of chemicals such as chlorine bleach or hydrogen peroxide.

Many gardeners choose to make their own compost tea using items on hand. Molasses, water, compost and various buckets and hoses are all the materials needed to create a rich tea without the use of chemicals. The process typically takes from 3-5 days and the resulting solution can be immediately applied.