I've been having a frustrating time with snow peas this year. The seeds sprout and grow well, put out flowers, produce a couple of pods and then start to die. The foliage slowly turns white, most of the flowers dry up and the pods that do develop are stunted. I've been growing them in large black plastic pots and large clay pots both in the sun and also in light shade. I've grown snow peas successfully in the past -- what is happening? It's driving me crazy because the plants are fine for weeks, then they fade away. I haven't been fertilizing, but the potting soil is fresh. I don't think water is an issue. I'm growing Oregon Sugar Pod II, in the S.F. Bay Area. Any thoughts?