Wednesday, September 15, 2010

Compost Tea

Seattle University has a great composting program, wherein food scraps are collected on campus in cans next to the garbage and recycle cans, and then two dedicated facilities gentlemen turn it into the good stuff. An exciting component of the composting program is the compost tea that is brewed by the Grounds crew and applied to plants on SU Grounds. I have the immense pleasure of brewing that tea with my coworker/mentor JM, and I took some photos last time I brewed to share the experience with folks.

This is the tea-brewin bit of the field house at SU. The 100-gallon brewer is on the left, and the 100-gallon sprayer tank to which we hook up the small tractor and with which we apply the tea is on the right. The shelves in the background have tubs with vermicompost, food compost, tea food, and mycorrhizae in them.

These are the magic additions we make to the tea - humic acid, kelp, and fish hydrolysate (less processed and FAR smellier than fish emulsion fertilizer, if you can even imagine that).
Here are the parts of the brewer, which we clean and dry on this super-organized pegboard. From left to right: cleaning brush for the tank, the filters that hold the compost, the bubblers that push air through the compost filters, the covers for the filters, and the attachment for the smaller bubblers to fit onto the larger bubblers.
Here is the trug in which we mix SU compost, vermicompost, and fish hydrolysate and let it sit for a few days.
This is what it tends to look like after a few days. It's just teeming with microorganisms. Mmmm.
Step one: fill the tank with water. Chlorine will kill the microorganisms, so it's important to use a chlorine filter or bubble the tapwater for 2 hours or so to let it off-gas.
Here's a closer look at the fish hydrolysate, which we add to the water along with kelp and humic acid.
Those things turn the water this color. Pretty nice, eh? The humic acid makes it smell like really good soil, which is what it should end up smelling like if the tea turns out right.
Put the top on the brewer and install the filters, and put that compost into them with some tea food (in the yogurt container on the right - JM sure does love Pavell's).
Here's how it looks with everything installed and the smaller bubblers turned on. It flows over the top when I brew, but not when JM does - I'm clearly an amateur.
...turn the large bubblers on overnight, and this is what you'll find the next morning. Yum! The whole field house smells like fresh earth and it's ready to pump into the sprayer and be applied to whatever lucky plants are chosen. 

1 comment:

  1. Whoo hoo, that is so intense! It does my little chemistry heart good to see what you are brewing up!