I've never had much luck with watermelons...the last time I tried to grow them they got big then cracked. I gave up for a year and then after talking to a friend who said I need better drainage and water retention because they were probably getting stressed, I tried again.
The soil is a mixture of cow compost, potting soil, and our local clay. I added grit to help with the drainage issue. I have corn and watermelon growing together - plus a bean here and there (I threw those in last minute because I honestly think they wouldn't grow).
Anyway, not all the vines, but some of them are yellowing a bit and the fruit just forms yellow. Anyone have any idea why? My friend said they might be getting too much water, so I held off watering them. Of course now we're getting torrential downpours.
Do they need some sort of amendment or supplement I can add? I do have one melon that is not yellowing and growing nicely....so not all are like that.
Maybe the corn is blocking them from getting enough sun?