37+ Brown Spots On Watermelon Leaves. If you see brown spots on leaves it is likely caused by a fungal infection. Could that be the case?
The leaves are large, coarse, hairy.
If not and the yellow / browning is happening at different parts, you may want to check the soil to see if its dry or saturated. If you see black spots on the melon (as pictured above), this is where sugar is seeping out and indicates a sweet melon. The leaves are large, coarse, hairy. The disease typically affects lower or mature tobacco leaves.