Compost and Manure Tea Brewing

It is well known that compost and compost teas are very beneficial for your garden. Gardeners have been making their own fertilizer for centuries, and there still seems to be confusion about using these teas and the difference between them. What seems to be confusing to many is the difference between manure compost and regular compost (without animal manure), if there is a difference and which is best and safest for your garden.

Compost Tea

Compost tea is produced in a number of ways, essentially straining compost through water. Compost tea is very beneficial to your garden. It contains many soluble nutrients such as nitrogen, phosphorus, and potassium. You are basically creating your own liquid fertilizer.

Manure Tea (Still Compost Tea...With Manure)

One huge misunderstanding, especially with new gardeners, is that manure tea should be made with raw manure. Raw manure can contain high levels of bacteria, such as E. coli as well as nematodes that will feed on the roots of your plants. Manure tea is produced by steeping composted animal manure, such as cow or horse manure. The same methods are used as making compost tea. Manure tea contains the same nitrogen, phosphorus, and potassium. Remember, the bacteria threat can be eliminated by properly composting the manure.

Using Manure in Composting and Tea

Farmers and Gardeners have been using manure in their fertilizing and growing endeavors for centuries. Using compost and compost with manure or any organic fertilizer will be beneficial to your soil. It is critical to properly compost your manure compost.

In 2004, the USDA - National Organic Standards Board published the Compost Tea Task Force Report. This report strongly cautions the use of raw manure in fertilizing teas. Ensuring that your compost pile achieves 150 degrees F will eliminate E. coli and other bacteria. Ensure that you turn your compost pile often to ensure 100-percent of your compost reaches the desired temperature.

Making Your Own Tea

There are probably as many recipes for compost tea as there are gardeners and farmers. Where there are a lot of deviations, the basic recipe is the same, depending on the amount you are making and the method you choose to make it in.

Passive composting or the bucket method is created just as one brews a cup of tea with a tea bag. Submerge a burlap sack filled with your compost into a bucket or other container of water, stirring occasionally. This takes up to 10 days to brew. Other popular materials to use as a tea bag are nylon stockings and paint bags.

Another method is to do the bucket method with a small air pump (like you would find for an aquarium), and the addition of microbial food and catalysts. Adding these components makes aeration very important. Sump pumps can be used to enhance the circulation.

Other methods used commercially or on large farms are the "through" method or larger commercial equipment. Depending on your need, there is commercial tea brewing available. The Appropriate Technology Transfer for Rural Areas (ATTRA) has a lot of information on their website regarding compost teas and has many companies they recommend for the purchase of composting and brewing equipment.

References

ATTRA - Notes on Compost Teas

Green, Doug - Doug's Green Garden, Compost Tea vs Manure Tea vs Compost Leachate

USDA - Compost Tea Task Force Report

Zimmerman, Bruce - Composted Manure Tea