All my vegetable plants' leaves seem to be steadily shrinking down to nothing. Whats going on?

I have several vegetable plants that I have in my garden. I have bean plants, okra, lemon gourd, bitter lemon and even papaya. All these plants we have grown well every year with great success. I live in Texas. They have all prospered despite the heat and I water them very well twice a day. I've seen leaves bigger than sombreros in the past. Now, for the first time it seems that these plants are shrinking. Their first leaves are all very large and healthy, but now it seems the leaves on the vines are shrinking gradually until the vine has no leaves at all. I have created a very strong structure with several strings that line it for support. The vines have plenty of support, plenty of sunlight, plenty of water, and I personally till the soil before I plant with various fertilizer and keep them well fertilized throughout their life spans. I am 69 years old and have grown plants since I was 8 in both India and America. I've never seen this problem before. We had some hail about 3 weeks ago but the leaves that could have been affected by it have already grown and are perfectly normal. Also, with the variety of my plants, I don't think it is a form of bug, but I am not discounting anything. Please respond. It hurts me to see my plants dying off like this. Some of my bitter lemons grew 2 feet long. I haven't even seen them that big in India. Now they stop growing at 4 inches. Please help.