Question: Does it hurt compost to leave it for a long time after it is done decomposing?

Answer:When compost is "finished," the nutrients are readily available for plants to use. However, this also means rain can wash, or leach, out the nutrients. Try to use your "finished" compost soon or cover it with a tarp until you can. Don't cover compost that is still in the process of decomposing, when the microorganisms doing the composting need moisture.