Composting is a relatively easy way to supplement garden soil using organic materials you might throw away. Before these handy ingredients are ready to feed hungry tomato plants or rose bushes, they need to be deconstructed with a little help from nature. Like a casserole fresh from the oven, homemade compost makes for a great meal if you're a hungry plant or shrub. Let's review some basic composting concepts and explore 20 unexpected household materials you can add to your compost pile.