It's been cold overnight here, too, but I think we're out of the woods now.
I scattered my watermelon seeds all over the place. I planted dozens and dozens- in my city backyard as well as up in the mountain clearing. Many of them were co-located in raised beds with blueberry bushes and fruit trees. I planted lots of seeds in a large pot with an excellent soil mixture, too.
Not much germination activity yet.
I may or may not have done this right, but I planted so many seeds, I imagine I'll get some robust volunteers. Only time will tell.