Compost tea is a great way to spread out your compost so it can reach more of the soil surface. It also encourages the growth of additional microorganisms. There are many important factors to consider, such as quality of compost and specific methods. Read on for an overview of the how and why of making healthy compost tea.
Worm castings
Some vermicomposters mix in their worm castings for added benefit. Compost tea can be derived from compost and worm castings separately. If you have a vermicompost, compost tea will make itself available to you at regular intervals before the rest of your compost is finished.
Take the worm castings, brew them, dilute them, and then spray the mixture on the roots of plants using a spray bottle. Do not use a spray bottle recycled from a chemical cleaner -- it could still have traces.
Combining worm castings
Other composters add their worm castings to their compost tea when they make it from their kitchen compost. Although the addition of worm castings basically makes for a more well rounded compost, you may have to wait for a full batch of vermicompost to form.
Since worms digest food using bacteria instead of stomach acids, the resultant castings are high in healthy organisms. Worm castings, in combination with kitchen compost, are an ideal source for the type of soil microorganisms that can break down hazardous soil contaminants. Worm castings also provide humic acid, another excellent food source.
To aerate or not to aerate?
One non-aerated method that works well for feeding potted plants involves compost soaked in water. Place a burlap bag full of compost upright in a bucket of water, and leave it for a few days. However, increasing oxygen to the compost tea by aerating compost has benefits that may outweigh the slight increase in work. It's well worth it for larger scale needs such as your outdoor garden. Aeration encourages the growth of even more healthy microorganisms and can be done with an air pump.
Quality
When deriving tea from your compost, consider that you're making a "liquid extract of compost that contains plant growth compounds and beneficial microorganisms," according to Oregon State University.
This is why high quality is absolutely critical. In order to extract nutrients, there must be nutrients to extract. Healthy plants are more adept at resisting disease, and they gain this health from the quality nutrients you feed them.