Peanut shells are a great addition to a home compost pile. They provide a good source of fibrous woody matter that can break down in the compost pile and act as a carbonaceous agent. Composting is simply the product of controlled biological decomposition of organic material, according to the California Integrated Waste Management Board. It is the control part that you need to understand when it comes to adding things like peanut shells to your compost pile.
Crush the shells by placing them on a flat surface and walking on them. This action will help start the process of breaking them down into soil. If you have a large amount of shells you wish to compost, you can do them in stages. Sweep them up into a bucket.
Cover the crushed shells in water. They will try to float but add enough water so that they can move around freely. Soak them for at least twelve hours or overnight. You can leave them for a few days for even better water absorption.
Drain the shells and add them to your compost pile. Since they act as a carbonaceous element and you want a healthy ratio of 25:1 of nitrogen to carbon materials, you will need to add a thin layer of nitrogenous material like grass clippings or kitchen scraps.
Turn the pile by mixing it up with a garden fork every few weeks to introduce air into the middle of the pile. If it seems dry and there is no change, add more greens. If it is stinky and wet, add more brown material, like crushed peanut shells.