Why does a compost heap get hot? + the secret ingredient
A compost heap will get hot as microorganisms break down organic matter. As microorganisms digest the organic matter the exothermic reaction heats up the pile. The compost pile itself acts like a blanket to keep the heat in and can quickly reach temperatures of 170 degrees Fahrenheit.
The basic reason compost heaps heat up is because of the activity of the microorganisms that break down the organic material in your compost. As they chew up and break down the green and brown material, they use up oxygen and release heat. This heat gets trapped in your compost pile and gradually warms up.
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