Loofah
Luffa Aegyptiaca 

days to maturity:
plant spacing: 1 plant staked on a fence or large trellis
sunlight requirements: 8-14 hours
look out for: very aggressive vine - make sure to have plenty of space for it to grow
harvest notes: 150-200 days till harvestable
perennial

Luffas belong to the Cucurbitaceae or gourd family, along with their somewhat distant cousins squashes, watermelons, cucumbers, melons, and the hard-shelled gourds. In this country, luffas are usually grown for loofah sponges so the fruits are allowed to mature on the vine until they turn yellow or brownish, and then peeled to reveal the matrix of tough fibrous tissues inside that act as wonderful natural sponges. Luffa-derived sponges are tough on dirt but non-abrasive and perfect for washing your face, body, dishes, floor, or car. Crafters even use slices of the dried sponge in soaps to create pretty and useful all-in-one luffa soap rounds. But in many other parts of the world the flower buds, flowers, and very young fruit (which taste pretty much like summer squash) go in salads and other dishes.