My compost pile finally hit 140 degrees and I felt like a backyard scientist

I've been turning my compost pile every week since early spring, trying to get the mix right. It's just leaves, grass clippings, and kitchen scraps from our house in Tempe. I stuck my compost thermometer in this morning, expecting the usual lukewarm reading, and the needle shot right up to 140! I actually did a little fist pump right there by the bin. It means all that work balancing the greens and browns finally paid off and the microbes are really cooking now. I think the key was adding a bunch of shredded cardboard last week after we had a big pizza night. It's such a small thing, but seeing that number made all the effort feel real. Has anyone else hit that magic temperature and noticed how much faster everything breaks down after?

3 comments

3 Comments

murray.rowan2mo ago

That hot pile is basically a microbial feast now (it's wild how fast things disappear once it gets cooking).

anna5671mo ago

Actually decomposition slows way down once a pile gets hot enough. Most of the visible shrinkage is just water evaporating, not the materials actually breaking down. The high temperatures kill off a lot of the microorganisms that do the real work, so the pile can stall out for weeks. If you want things to disappear fast, you're better off keeping it cooler and turning it more often. That rapid collapse you're seeing is mostly just physical settling, not the microbes having a party.

anderson.jason2mo agoTop Commenter

Watching it shrink overnight still blows my mind.

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