At some point in your life, you've probably encountered a loofah sponge. They work pretty well for scrubbing, I think. A year or so ago, I learned that they're a type of squash, so I tried them in my garden this year.
They've been vigorous and showy, with scads of yellow flowers that the native bees love, and gigantic fruits that drew lots of questions from neighbors. It's late October, and despite a near-frost last weekend, these plants are still putting out new fruit.
The seed packet says "Compact Loofah Sponge Gourd". I'd like to know which part of these are supposed to be compact. The squash I harvested was two feet long (60cm) as you can see in the photo below. It's not the largest I have. The plants themselves ran everywhere -- into and over the tomatoes, over the 12' tall sunflowers, and into the cowpeas. (The cowpeas have also been really aggressive and I'm content to let them fight it out with the squash for supremacy. Go ahead, fight. Feel like you're winning. Frost is coming.)
According to the seed packet and advice I've seen on the Internet, I'm supposed to harvest these when they're brown on the outside. Ideally I should be able to hear the seeds rattling around inside. Mine haven't dried particularly well on the vine. Of the five I've harvested so far, all had a significant amount (maybe as much as a cup/250ml) of fetid liquid inside. The skins were rotting rather than drying, and poking/scratching a hole in the skin allowed the liquid to escape. (Watch out for your shoes!) This might have to do with the amount of rain we've received, including from Hurricane Delta.
Peeling them has been a mixed bag, with some of the skin coming off in big, easy sheets, and other sections requiring scraping with a fingernail. Once peeled and dried them in the sun, the seeds start to come loose. Squash usually have lots of seeds inside, and these are no exception, so if you grow these once, you can have them forever.
And yes, you can eat them, but only when they're small. I tried one and it was just OK. There's enough other good things to eat; I'd rather let it grow into a sponge.
My only disappointment with these squash is that they're a completely different genus from Long Island Cheese Squash, so I can't cross them and get rich selling pumpkin spice loofah sponges.
Note: I wrote a followup post about my loofah harvest.