For several years I was able to grow decent-sized Big Max and Jack O'Lantern pumpkins with little difficulty. But starting a few years ago, I began to have a consistent problem with the leaves yellowing, followed by the leaves and eventually the vines dying.

The problem begins very soon after sprouting, with the leaves gradually changing from a healthy dark green to a uniform pale yellow-green, then turning yellow, then browning at the edges, and finally dying. The condition begins with the earliest leaves and moves toward the end of the vine, even as the vine continues to grow.

The other symptom is the appearance of tiny "bleached" spots scattered over on the front of the leaves, shortly after the yellowing begins. The spots are flat, and the backs of the leaves are normal.

This year, I planted the seeds in purchased garden soil, thinking it might help if there was a soil-borne disease, but it made no difference.

The photo shows plants that are about one month old, displaying various stages of the problem.

Any thoughts would be much appreciated!