Well, it's a mystery no more: the squash that popped out of my compost is a miniature pumpkin. With a little luck not only will I have my fill of squash blossoms to eat, but I will also have my Hallowe'en display and pie filling for free!
As you can see from the picture below, squash plants can be quite invasive. Yes, that is one lone plant that has invaded an entire bed and is attempting to jump into the tomato patch. Just for refence's sake, the 'pumpkin patch' is about the same width as the compost bin in the background, and three or four time as long.
The other plants in the bed are barely surviving, but I can't even go and rescue them since the squash is so prickly! Next year, I will have to cull all compost volunteers.