Can you imagine a tree that grows soap? In Asia, a species of the lychee family grows nuts that people have been using to make soap for centuries. The soap nuts contain a natural ingredient called saponin, which is a natural surfactant that suds up and can remove dirt, grime and odor from clothes. Online sites like abesmarket.com sells soap nuts that you can use for laundry. Simply place a handful of the dried soap nuts into a sachet and toss it into the washing machine. It will make the water sudsy and get your clothes sparkling clean. After 10 uses, simply toss the nuts into the compost bin, and they'll completely biodegrade.