There is one other issue with leachate which is critical if you are going to spray it on your plants. Anaerobic organisms will start growing in the material if it isn’t constantly being aerated. These organisms can carry diseases to your plants. Even compost tea has a very short shelf life, measured in days, after aeration stops for the same reasons.

So unless you use the leachate within days of it being generated, don’t spray it on your plants. You can use it as a liquid fertilizer, however, and I do in my own gardening practice. It is loaded with nutrients and the anaerobic organisms won’t survive in a healthy compost fed soil mix. So they shouldn’t be a threat to your plants. If you are uncomfortable with feeding it to your plants, then add it to your backyard compost pile. The aerobic organisms in that pile will thrive on the nutrients and you will get better compost for it.

danh
Dan Hafeman
Full Circle Farm Sunnyvale Garden Manager