Question
I have been growing a pumpkin plant in my vegetable garden, and it was growing great until about three weeks ago. The leaves of the plant started to turn yellow, then brown on the edges and die and fall off. From what I read online, the only thing I could find was that it might be powdery mildew, since I had been watering the plant with a sprinkler therefore getting the entire plant wet instead of just at the roots, and the fact that the leaves were whitish seemed to make powdery mildew fit the situation. However, after awhile it seemed that there was no powdery looking white stuff on the leaves. Also, the main stem (I suppose that's what it's called, basically where the plant comes out of the ground) of the plant is now cracking, and seems to be dying; it looks dried out. I've been watering the plant at the roots now daily for awhile but it's only getting worse. Now the cucumber plants next to the pumpkin plant are starting to have their leaves turning yellow in spots as well. I really have not a clue as to why my plants are doing this or if it will continue to get worse, but the flowers seem to be blooming and look quite healthy to me. Just the pumpkin plant's main stem that's kind of worries me because if that part dies then the rest of the plant will follow. I have no if I did something wrong or if there's even anything I can do to fix the plant. What can I do?
Thanks for the help,
Julia

Answer
Julia:
For all of your vegetable plants, it is best to do your best to keep the leaves dry. This can be done by drip tubes, soaker hoses, or just irrigating in the furrows.  If you have to water overhead, do it early in the morning, so the leaves dry off by late morning or mid day.  This cuts down on the diseases that affect the leaves.

Powdery mildew, a fungus disease starts out as white "fuzzy" patches or blotches on the leaves.  As it gets worse, the leaves just seem to "burn up".  I usually don't see the leaf get yellow.  This may be caused by an unfavorable root environment (water and/or fertilizer imbalances).  Always be sure to get your garden soil tested BEFORE you install your vegetables. This test can be done through your local county Extension office free of charge.  It will tell you what you need to add to grow the best vegetables. You can carry your sick plants into this office for a diagnosis.

Leaf spots on vegetables can be caused by many disease organisms and many spots look the same. A good general product for many vegetable diseases is DACONIL.  It contains chlorothalonil.  This product works best if you get it on the plant before the disease gets started. It is normally sprayed on the plant.  Be sure to read the label on mixing and applying.  Be sure to check with the garden center/or nursery for advise on this and other products.

Regards
Steve