Monday’s Guests – Compost Tea

Brad from Highly Uncivilized has a fantastic post about making compost tea that he wants to share with us. We haven’t really gotten into making compost tea here because we use our animals as composters, but for those that do make regular compost sans animals this is a fanastic way to increase your soil fertility.

Compost Tea 
Improve your Soil Health One Cup at a Time 

As with everything, there is even controversy around how to make compost tea.

Compost Tea Pot

The two basic camps are anaerobic, or aerobic, and there is “scientific research” to back up both sides that you can easily find on google.  The aerobic method “brews” beneficial bacteria with added oxygen, introduced by something like an aquarium pump, and this environment favors the bacteria that requires oxygen.  Anaerobic is the opposite.
After reading way to much on this topic we invested in some supplies to start making the aerobic kind of compost tea.  Two books have really started to reframe my mental approach to yardening, The One Straw Revolution, and Teaming with Microbes.
I’m now understanding why people are making such a fuss about till versus no-till, and the negative impact to your soil life even from something as simple as a basic chemical fertilizer.  As a side, this guy gets into the Highly Uncivilized Hall of Fame for doing no till in an old refrigerator.
Aerobic compost tea increases the number of beneficial bacteria and other critters, which results in naturally healthy plants with good yield.  Most importantly it creates or strengthens a soil web of life that controls disease and creates it’s own fertilizer for the plants.  Some people swear by it, some people say it doesn’t work at all, and one person said it killed some of his plants.  Test some on your plants first just in case.  We are having positive results already and have not seen any plant mortality.  The most positive results so far have been controlling a powdery mildew (or something that looks like it) and some big plant growth.
This kit cost under $20, but you can probably do it for less.  I couldn’t find an aquarium pump at my local pet store or garage sale so I bought a new one from Amazon because I had a credit there.  I bought a two outlet air pump, 10′ of plastic tube and two air stones.  I also got a five gallon plastic bucket from the garden area and a big rock to hold the air stone down.  Here are the pics of the Tea Pot, and some white plant disease we are trying to kill.
You will also need:

  • A couple of cups of compost – I use worm castings from my giant worm bin.
  • Water with no chorine.  Let your bucket of water sit out in the sun for a couple days and you should be fine.  I use a 5 gallon bucket which needs 4 gallons of water.
  • A source of sugar.  Most sites recommend Molasses because of the additional nutrients available to the microbes.  I’m using white table sugar, which works just dandy for other bacteria like Kombucha and seems to work fine for this.  I use a tablespoon per gallon.

Take your bucket of water and turn on the air pump.  Mix the compost and the sugar and add it to the water.  I let mine run for about two days.  It should have a sweet soil smell and it will produce foam and bubbles.  When it’s done you can use it as a soil drench or a foliar spray.  I do both.  I also water it down a lot but I’ve also put it on the plants straight.

spinach with some disease
Spinach with some disease

Every article and book I read has different ways to do this.  Recipes can be for bacterial dominant tea or fungal dominant tea.  Didn’t know this would be so danged complicated, eh?  Here are some articles to give you a well rounded approach to investigating and experimenting.
Compost Junkie
Dirt Doctor
Captain Compost
Don’t run it too long or the bacteria run out of food and start to die.  Don’t do it without oxygen or you grow bad bacteria.  If you add other stuff like fish emulsion then something else happens but I don’t remember what.
I’m trying to keep it simple.  Sugar and oxygen feed good bacteria that promote balanced healthy soil.  The end.

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