Wow at first sight of mildew on the leaves I sprayed but the mildew completely took over forcing me to remove the entire harvest. Is this normal I only wated the soil not the leaves and had the crop climbing up. Maybe weird weather in CA?
If I recall the weather down there it was unusually rainy and damp for a prolonged period of time at least by Ca. standards. It takes dampness to cause the mildew. We get it every fall on summer squash etc in the NW, so it is probably because of the weather this year. Sorry about your crop.
Next time try Super Sugar Snap. It's MUCH more resistant to mildew. I've grown it side-by-side with regular Sugar Snap and the production and flavor are similar. Powdery mildew is usually what ends my season when it gets hot and humid.