I did a little research and all I needed was a sunny spot where the vine could grow. So come spring, I planted several seeds by my back fence where they flourished. They produced big yellow flowers that were not only beautiful, but attracted bees as well. When the flowers were pollinated they produced gourds that grew quite large. They went from bright green to brown when they were ready to harvest in the fall. I could also hear the seeds move freely inside when shaken.
Loofahs are actually a vegetable native to South America. For sweet, edible fruit they are best harvested when small and before they become fibrous. I have never harvested them early as a vegetable.
I use them in the shower, as non-abrasive scrubbies in the kitchen, and as drainage tools in the bottom of planters. I have also made fire starters out them with paraffin wax.
If nothing else loofahs are a great conversation piece!