Little dead watermelon

This is what happens, and now it happened in our greenhouse. The first lille watermelon has faded away. Why? At the same time a lot of the watermelon flowers also faded away. Now I keep doors open – it could come from humid air. And yea, I do know you (almost) can’t grow watermelons in Denmark. Everybody tells me so, allthough you can find the seeds in any seedrack.
Well, anyone is free to try for themselves.

PS. Two seasons ago it succeeded.