So, I can buy ready made compost teas? How do they work, as far as feeding goes? Do they replace the nutes, or do they supplement them? If we use them, do we have to be wary of burn or over feeding?
It's not "ready made" as in already brewed liquid tea or anything. All my research says NOT to buy liquid teas. A tea is supposed to be alive, so sitting on a shelf for months isn't what we're looking for.
Basically it's a dry mix of a bunch of ingredients. It's mostly really good compost and earthworm castings. From my understanding, it's the compost and EWC that provide an array of dormant microbial life, as well as carbon, other elements/minerals, and humic acids. Then there's a ton of other ingredients such as rock dust for a complete array of minerals, kelp and alfalfa meals for plant growth regulators like auxins and cytokines, etc. Finally, there's some sugar crystals in the mix to feed the microbes and allow them to reproduce. There's more good stuff in there, too.
So then you just follow the instructions on the package. You'll need some sort of brewing vessel with a strong air pump and diffusers/air stones. Their instructions call for a 5 gallon bucket, but I don't need that much. I brew in a 1 gallon pitcher. Just maintain temperature (~70F) and let it bubble anywhere from 4-24 hours. The sugary water wakes the dormant microbes up and they get to work eating the compost and other ingredients and start reproducing. Eventually, there will be a huge head of foam on the brew which is apparently a result of the microbial activity. Whenever you decide to finish the brew, you gotta use it immediately, as it's full of life and needs lots of oxygen.
Boogie Brew says you can use it straight without ever burning(assuming you used their recipe ratio, 1 cup dry mix to 5 gallons water). For soil drenching, they recommend diluting it 1:10 if you are already using other fertilizers, or 1:2 once/twice weekly as a "stand-alone tea." Interestingly, they caution against using liquid fertilizers on the label and advise to use half or less of the nutrients you'd normally use. I think this is because the tea enables your plant much easier access to what's in your soil.
As far as replacing or supplementing nutes... They give a few different scenarios on their label.
For soilless/hydroponic growing using liquid fertilizers, they say to use 1:10, and to cut back on other nutrients, "700ppm max!"
For those who grow in rich soil and occasionally top-dress, "feed half-strength tea once or twice weekly. No liquid fertilizers!"
You can also foliar spray it at 1:5.
I imagine if you're looking at it from the NPK perspective, it probably has a good amount of P in it as rock phosphate is one of the ingredients. I think of it like a probiotic for plants. It has a collection of "good" soil microbes, that will compete with the "bad" ones. So it'll inoculate your growing medium with life that will form a symbiosis with your plant. More than that, the microbes eat a lot of the good stuff in the dry mix and contain it within their cells in easy-to-absorb forms. So even if your soil has plenty of life, those excess microbes in the tea that can't get a foothold will get slaughtered by the resident microbes, unleashing tons of readily available materials and energy. At least, that's
my humble understanding of what's going on...
