I have various vegetable plants that are dying for no good reason. Pepper plants that are producing and I've even harvested some. Tomatoes doing the same. Zuchinni doing great. Then for no reason some, not all of the plants look like they're undewatered and just die. They are in all kinds of beds: raised, back to eden (woodchips) wicking, even 2 separate compost bins. 4 zuchinni in 2 compost bins and one dies.10 pepper plants in wicking beds and 4 die. I'm talking full grown plants. Any suggestions?