Please see picture - the leaves on the older stems don't seem to be too happy and I'm seeing the same on the tomato older leaves. Could the cooler temps have anything to do with it? The temps have warmed up and the newer leaves are looking good. Any suggestions?
http://davesgarden.com/community/forums/t/1002586/
On the thread I linked above, I posted several links to sites for watermelon diseases. See if you can't find your problem there. Also, what kind of soil is it planted in? What kind of amendments have you added? What variety is it?
