|my tomato plants leaves are curling up and though the plant itself is still green it is lightening in spots like it is loosing clorophyl.|
|The shapes of tomato leaves vary depending upon variety. Some leaves are smooth and look like the leaves on potato plants and others are wrinkled and more 'tomatoey' looking. The weather can also have an affect on how leaves look. Heat can cause the leaves to curl. Unless the leaves are distorted, thick, or curl upward, I wouldn't be too concerned about their appearance. However, if the leaves are developing blotches, you could be dealing with a disease such as fusarium or you're seeing the signs of fungal diseases brought on by wet or humid weather. If the veins of the leaves are dark green but the remaining tissue is yellow, it usually indicates a need for iron. There are so many possibilities that it's difficult to diagnose just from your description. There's a diagnostic publication online that might help you hone in on the exact symptoms you're seeing with your plants. Here's the web site: http://vegetablemdonline.ppath...
It's a long address so you may have to copy and paste it into your browser's window. I hope you find it helpful.