I’ve been reading a lot about garden ecology these last few months. Garden ecology focuses on the biology of each zone of the garden: deep soil zone, root zone, rhizosphere, leaf zone, outer environment. The healthier each of these zones are, the better your plant grows. What I’ve come to learn is that healthy soil can’t be determined by just measuring the nitrogen, phosphorous & potassium (NPK), but is completely determined by the health of the biological activity, or lack thereof, of the soil & surrounding zones.
Worms, bacteria, protozoa, nematodes, fungi, and other microbiological creatures are needed to make healthy soil. Of course, some of these creatures are culprits for causing disease, but diversity and volume are key for keeping the pathogenic organisms in check. In fact, plants are more likely to get diseases if they are not present. For instance, there is a nematode that penetrates a plant root to feed, but scientists found that fungal hypha can trap this nematode to prevent it from getting into the root. And then there are the beneficial nematodes that you add to your soil to kill fungus gnat larvae and parasitic nematodes and other larvae.
Not only do these organisms prevent disease, but they also act as time-release fertilizer pellets. By consuming other organisms, organic material and plant exudate, they immobilize the nutrients and hold it in the soil. This way it doesn’t sink down out of reach, or leech out of the soil. These organisms excrete wastes, become food for other organisms, or eventually die, releasing these nutrients back into the soil for the plant to take up.
Adding compost, as long as it wasn’t hot composted, to the soil promotes biological activity, but if fertilizer is being added to the soil also, then the organisms will be killed off. The byproduct of fertilizer usage are salts, which build up in the soil and kill the organisms.
After determining that my soil lacked biological activity, I went looking for ways of increasing the organisms present. I could buy worms, nematodes, make compost, etc., but I had heard a little bit about the benefits of compost tea and wanted to try it out.
Compost tea is basically a liquid that has sucked out the nutrients & organisms that were in the compost, but if it’s actively aerated and fed some sugars, then you get an exponential increase of what was in the compost.
So I got myself the materials and made a compost tea brewer:
- 5-gallon bucket
- 1/4″ soaker hose
- 1/4″ tubing
- air pump
very cheap & easy! It only takes a day or so to make a batch from start to finish. The tea has to be used right away, when you stop aerating it, so don’t bother buying any that you see at farmers’ markets or the store. it can be used as a soil drench or in a sprayer (as long as it’s strained first) as a foliar feed.
I used it when i potted up my tomato starts, actually i only used it on half of them – and wow! the ones that got the tea are much bigger and stronger. I added it to all of them when I planted them in the garden, so now they are all pumping.
From what I’ve read, if your soil has been subjected to lots of fertilizer usage, then the compost tea should be sprayed every few weeks all summer long, then next summer you can spray once per month. Eventually, as the biological activity gets going, you only need to apply it at the beginning of the summer and when the flower buds are set, and then at leaf drop.
Naturally there’s a lot more to the tea making, like whether it’s bacterial, fungal or balanced, but I’m just beginning!