our watermelons are white not red inside. what is the problem?

Question

we are growing sugar baby & black diamond watermelons in Galveston County, Texas.  they get enough sun and they have been growing from seed and seedlings for over 4 months.  they look ripe but when we cut them, they are white or mostly white & some red inside, not wholly red and ripe.  what is the issue?  we've only gotten a few good ones, most of them have all the signs and length of time correct to be ripe, but aren't.  thank you.

Answer 1

This week they had a show on TV about those small seedless watermelons, the white inside one is the male & the pink to red is female.............need both to grow the red one and the white one is not sweet.