Can anyone tell me how long compost tea is effective? Everything I've read says its most effective when its first made i.e still fully aerated. How long after that is it still useful and can it keep for long periods? I'd like to make up big batches rather than keep making smaller amounts when I need it.
I've been wondering about this too. The compost tea "industry" is becoming, well, a big, commercialized industry. Producers are bottling and selling the stuff as some kind of miracle potion, no matter how long it sits on the store shelves. I'm pretty skeptical about the stuff that TerraCycle is flogging. The people at SoilfoodWeb say "Maintain tea fully aerated as long as held before use" ( http://www.soilfoodweb.com/03_about_us/approach_pgs/c_05_cmpst_tea_standards.html ) but I couldn't find any data on their site about how fast the tea "dies" after it's been bottled. Google didn't come up with anything resembling research, but maybe I'm using the wrong search terms ("compost tea" + efficacy + bottling). Work for someone with more time and patience.
Yes I have also searched quite hard on the web and found no reference to shelf life.. I have been using worm tea for a few years now that has never been aerated and had very good results but have been told recently that it needs to be aerated and used within 4 hours.......i've never aerated and my plants respond very well to what their getting.
Make your own http://www.dep.state.pa.us/dep/deputate/airwaste/wm/recycle/Tea/tea1.htm http://heartgarden.com.au/composttea.asp Liz
The different opinions are often due to different meanings to "compost tea". "Aerated compost tea" is made in about 24 hours from a smallish amount of compost in water with added nutrients, and lots of added air during the process to grow "aerobic" microbes. This stuff needs to be aerated until you apply it, or the microbes will die or go dormant without oxygen...about 3-4 hours without the aeration is the maximum I've ever heard for use of this product. Those added nutrients are an advantage if the process is controlled thru to application on the garden, but may be detrimental if oxygen is reduced, resulting in anaerobic byproducts that can be quite damaging. At best, a non-aerated "ACT" will be much less beneficial than one kept oxygenated until application. "Compost extract" is made from just a larger quantity of compost mixed well in water to extract microbes and nutrients. This stuff can be stored effectively since the microbes aren't mostly active and therefore don't demand oxygen. Much of the benefit seen is also from minerals and other chemicals in the solution, not the active bacteria and fungi that the aerated version provides.
