The following was posted here on What About Watermelon? awhile ago, but I hear this question a lot, so I’ve decided to repost it.
KEITH O. FROM PENSACOLA, FLORIDA, ASKS: I know seedless watermelons don’t have the big black seeds in them, but what’s up with those small white seeds? Are those seeds? And if they are, how can the watermelon still be “seedless”?
Good questions, Keith. I’ll answer your second inquiry – are those seeds? – by confirming with confidence that they are not seeds, thereby allowing seedless watermelon to retain its name.
Seedless watermelon gets its name because they contain no mature seeds (the black ones). The little white things you see are the remnants of seed coats (where a black seed was supposed to be, but was not allowed to mature).
Just like regular seeds, these seed coats are perfectly safe to eat. Unlike regular seeds, you can eat them along with your watermelon and not even realize they’re there.