Compost Tea Research


Does Compost Tea make certain leafy vegetables grow bigger or not?

Effects of Aerated Compost Tea on Swiss Chard, Kale & Lettuce Production in Virginia

A Producer Grant sponsored by Southern SARE (Sustainable Agricultural Research & Education) ending in March 2025.

Microbial Populations in Compost
Compost Tea / Extract

Does feeding the microbiology in the soil really make a difference? These results were from teas that were unfed.

This first batch of vermicompost was rained on and not turned due to fear of breaking fungal strands. This resulted in almost anaerobic, too-wet conditions. The tea that was brewed from it was not fed any microbial foods and while resulting in no pathogens, had hardly any beneficial bacteria in it.

Vermicompost Microbiome June 2023 vs.
Compost Tea Microbiome June 2023

The second batch of vermicompost was kept indoors. While resulting in a more robust compost, did not produce a robust tea according to test results. Compost tea sampling 48 hours post-harvest may have skewed true results.

Vermicompost Microbiome November 2023 vs.
Compost Tea Microbiome November 2023

Literature Review of Compost Tea Research

You can read a very broad summary of the studies below here.

I've organized the Compost Tea literature into two categories:

Click on the images above to Zoom in on these two topics.


Studies on Benefits of Compost Tea Application

1. Plant Growth Promotion

Annual Plants
Perennial Plants

4. Nutrient Enhancement

Nutrient Enhancement by Eisenia foetida in compost and compost tea by Ed Stockman (Organic Agrosystems Research)

A microbiome analysis of bacteria and their populations according to microbial starter (feed) in compost tea

Microbial Starter for the Enhancement of Biological Activity of Compost Tea

Does compost tea really multiply the biology in the original compost it's brewed from? And if so, how much greater are the populations? How much and what do we need to feed the good bugs for them to grow?

Also check out "Table IV: Nutrients and Heavy Metals Composition of Compost Tea Alone and Microbial-Enriched Compost Tea, at Day-3 of Brewing" in this study.

How to Brew Compost Tea

a Compost Tea Podcast Course
courtesy of Troy Hinke of Living Roots Compost

Elaine Ingham's Work on Compost Tea

Dr. Ingham's comprehensive manual on making, applying, and assessing compost tea is now available in its 5th edition. A must for any user of compost tea.

National Organic Standards Board
Compost Tea Task Force Report

What is legally deemed as safe compost tea by the USDA?

Notes on Compost Tea

Soil researcher Steve Diver's comprehensive notes on Compost Teas, literature review until 2002, and slides to his presentation. Really good pictures of the biology and cool compost tea facts in this one!