Since it's starting at the center, I would guess 2 possibilities: 1. Fungal disease which requires fungicide treatment 2. Aging and decline of the plant. Perfect vitality would prevent decline before frost. If it was primarily a nutrient shortage, I would expect the growing tips to show it.

I saw your photos and your post on the vegetable forum. Your bigger issue is that overall it just looks like the watermelons aren't thriving. Not sure if it was the soil, food, weather, whatever. Not sure where you are located, but if you have a long season you might still get a crop. The smaller issue is the brown spots on the leaves. Like I said earlier, I have the same problem, but usually doesn't start until late, and the melons are almost ripe. I just removed all of my infected leaves and gave a good drench of daconil. IMO it's a disease because I saw some of the spots on old and young leaves too.

Hello all! My first post here. Glad to have found this thread as I have also planted some watermelons this fall (along with some pumpkin and volunteer 'compost' cantelopes!) My question/concern is: I planted my seeds on July 24, and have had good success with flowering, bees, and fruiting. However, in the last week or so, I have not noticed any further growth. I have one melon that is as round as a tennis ball and 8' long. This is about the size I got them last time I tried watermelons before they started to shrivel up. I laid out black weed cover as a 'mulch' before planting, which seemed to help a lot as the seeds came up really fast. Both the watermelons and pumpkins leaves are yellowing (a lot more on the watermelons). I think I water them pretty good, and I read to let the top 1' - 2' dry before watering again. I am wondering if I should take the 'mulch' cover off to allow the soil to dry more. I am attempting to fertilize with by a specific schedule according to some info I found online (but some say more potassium when fruiting starts, other say more phosphorous). Anyway, sorry for the long post. I am at my wits end as I can't find any specific info online, and don't really know anyone here in NEFL who grows them successfully. Thanks in advance! Here is a link that might be useful: My Blog

Agree. You are very likely over-watering, keeping the soil too wet. Thus the fungus development. It is a common problem for many when growing things from seed since most seem to believe that if a little water is good, more must be better. Not true. And little seeds in a big cup of mix only encouraging more over watering because all that potting mix retains more water than the young seedling can handle. It is best to keep the ratio of seed size to container size balanced when possible. It is easy to get rid of just by cutting back on the water and allowing the soil surface to dry out and no need to drag out the big guns like fungicide to kill it. Improving the air circulation around the seedlings can also help. Check out all the FAQs and discussions over on the Growing from Seed forum here for more tips. Dave