I planted a few seeds in some plastic pots yesterday, and one of them was a bush sugar baby watermelon seed. I planted it in some topsoil in a pot that used to harbor an arborvitae, (it's either a 5, or 10 gallon pot. I'm not sure which), and unsure about whether it will have enough room for its roots to sustain a big enough plant to bear fruit, I thought maybe someone on spam could help me out.

Do you guys think I have a shot at getting the plant to grow a watermelon?

Also I was wondering if anyone else was in USDA hardiness zone 5, and can tell me if it's too late to plant some corn?