My Watermelon vine has gone wacko over the past month with new fruit but I worry that I will run out of summer before they are ripe! This is my first year growing them and so far I have harvested a few melons - (too early, I think) that were really pale pink inside what a shame!. Now I have the largest one yet that still has the green tendril and has not stopped growing. Do I cover when frost threatens (duh)? or can I pick and it will become ripe over time?
I'm no expert on watermelons, but I believe they need to fully ripen on the vine. They are frost tender, meaning you could try to protect them but I'm not sure they would survive even a slight frost.
Hopefully one of the resident experts like Farmerdill will chime in with a better answer for you - lol. I'm in Phoenix, so no worries about them experiencing frost unless you plant 'em too late...
locakelly is correct, they need to ripen on the vine. They do not do this very well when the day shortens and the temps fall, so covering them if they are very far from ripe is problematic. On the other hand the flesh of an unripe water melon makes excellent preserves. The old folks grew citrons expressly for preserves, but unripe watermelons work about as well.