Compost Tea Basics
Compost Tea is a nutritionally rich, well-balanced, organic supplement made by steeping aged compost in water.
It can be used as a root and/or foliar feed. It is also noted for its ability to control various plant diseases, blights, molds, wilts, etc. when used as a foliar spray. It has been reported to repel and control certain insect pests and limit their damage when used on a regualr basis, and to encourage the growth of benefical soil bacteria which results in healthier, more stress-tolerant plants.
There are several different recipes for compost and other tea's depending on what you are trying to accomplish. A web search will bring up lot's of variations for specific problems. You can add all kinds of suppliments like fish emulsion or powdered seaweed to make it into a balanced organic fertilizer.
Recent research indicates that using some kind of aereation and adding a sugar source (unsulphered molasses works well) results in an excellent product that extrcts the maximum number of benificial organisms. This aereation is crucial to the formation of benefical bacteria and the required fermentation process.
Using well made, high quality compost you can brew up a mild batch in as little as an hour or let it brew for a week or more for a super concentrate. A good median is to let the tea brew for 24-48 hours. When it begins to smell "yeasty" you can stop and apply it to your plants.
The tea can be used as is as a root drench or strain it out thru a fine mesh, dilute with dechloronated water and use it as a folier spray.
The following factors will determine the quality of the finished tea:
Use well-aged, finished compost - Unfinished compost may contain harmful pathogens and compost that is too old may be nutritionally deficient.
The contents of the compost - It should be balanced and of good quality if using purchased compost. That which contains some portion of aged animal manure apparently remains biologicaly active longer than compost made only of plant matter but it isn't required. (It is important to note that COMPOST TEA AND MANURE TEA ARE NOT THE SAME THING. Manure teas may be made in the same way but are not generally recommended as foliar sprays and are not as nutritionally well-balanced.)
Method of application and weather - A pump sprayer or misting bottle works better than hose-end sprayers for large areas or for foliar feeding as they don't plug up as easily. The beneficial miroorganisms are somewhat fragile so it is important to note you should avoid very high presure sprayers for appliction. Re-application after rain is necessary and one should avoid applying to the leaves during the heat of the day. Root feeding is not affected by the weather.
Thanks to all who contributed to this piece.