We can grow watermelon up north cold short season. I did pretty good with sugar baby but best melons I've ever had few yrs running is blacktail mountain developed by Sand Hill Preservation Center. I didn't get them from there, have bought chickens from him just never seeds. Got them from Baker Creek. Tons of small melons. This yr all my plants died, had melons but died. Had a super infestation of cucumber beatles this yr, they really liked them and my pumpkins loaded up in the flowers. Neem oil didn't save the watermelons but my pumpkins are doing great.