Now that the tomatoes have recovered from their phosphorus deficiency they have moved onto magnesium deficiency. The celebrity tomatoes are fine, it's just the orange paruche cherry that's affected. Purple leaves have been replaced with yellow leaves. From Wikipedia:
Symptoms include, yellowing between leaf veins, which stay green, giving a marbled appearance. This begins with older leaves and spreads to younger growth. Can be confused with virus, or natural aging in the case of tomato plants. Fruits are small and woody.I found a simple epsom salt recipe online, 2 tablespoons of epsom salt in 1 gallon of water, and applied it to my plant about a week ago. It seems to have done the trick, the yellow is not as pronounced as before, but just to be safe I'll continue to apply the epsom salt solution every 2 weeks. I'm actually quite thankful that this is the problem. For several days I was worried that the plant had a virus and that I wouldn't be able to eat any homegrown cherries this year. They're my 2nd most favorite thing to grow.