I raise three or four plants every year. Like a zucchini or a cucumber, it likes to spread out with little regard to another plant's personal space. Here is last year's crop.
Early in the summer, the loofahs remained neatly on the trellis:
But then they wandered over to the basil:
Cozied among the tomatillos:
And hung out with the butternut squash:
Harvest time was a regular treasure hunt. But I ended up with about 20 loofahs from my four plants.
This is what they looked like late in the summer. I peeled back some of the rind so you can see that it is, indeed, loofah.
After a frost, I could more easily peel the rind off the loofahs. I let them dry, then cut the loofahs into smaller lengths and shook out the seeds.
It's completely optional, but I like to soak the loofahs in a bucket of water with a splash of bleach to even out the color.
And finally, here is the finished soap. I'm calling it Garden Fresh. It is a blend of tomato leaf and lettuce fragrance oils, colored with a touch of chrome oxide and tomato paste. My loofah soaps are always a little more "rustic" looking, partly because it can be hard to get the soap into every little bit of loofah and partly because I want the loofah inside to be visible.
I'm already starting loofah plants in the house with some of my saved seeds and in another month, the cycle will go around again. Whew.