Compost Chemistry

A compost heap gets hot. Grade four is old enough to ask why and to measure it.

A long probe thermometer pushed into the middle reads well above air temperature if the heap is working, and if it does not, the heap is failing and the class can diagnose why. Too dry, too wet, too much brown, too much green.

The page has a two week temperature log, a moisture test by squeeze, and a diagnosis chart. It also has the four ingredient ratios in plain terms. Our first heap ran cold for a month because it was all leaves, and the class fixed it by adding kitchen waste, which was a better lesson than a working heap would have been.