Hi and welcome, Genia. You definitely were a little early in planting tomatoes for optimum growth in Florida. I just planted seeds for my new tomato plants last week, and they will bear tomatoes for me all the way through the winter to about May. I don't even try to grow them in the summer for a couple of reasons - first the heat tolerant ones have not tasted all that great to me, and some of them never bore fruit even though they said they would. Second, there are so many more blights and fungal woes floating around in the summertime that even the best-grown plants will just up and die over night if they get one of those infections. You can also start new plants indoors in January and grow them through the spring for a nice harvest if you lose your winter plants. I cover carefully on cold nights to keep mine setting fruit all winter.
Yes, what Tiffany said about predators for your pest bugs is so important. If you spray, spray, spray and kill off every bug you see then the beneficial bugs (things like ladybugs and lacewings that eat other bugs) will never get established in your garden. So please, suffer through this first little glitch of leafminer damage, grow your plants big and healthy and they won't die from leafminers.
I go through the garden maybe once a week and spray a mild soapy water solution on the undersides of the leaves of my peppers and tomatoes in the evening. This helps keep down things like aphids and whiteflies, but doesn't murder too many beneficials including bees and butterflies that are more active in the mornings.
I must be honest here and tell you that I've completely given up trying to grow cucumbers, and also any kind of squash or melons here in Florida. I suppose if I brought one of my Earth Boxes into the pool cage I might have a chance but out in my garden, there are just too many pests to keep ahead of on those, plus they are very susceptible to powdery mildew, a very fast-growing fungal leaf disease.
Your tomato problem is caused by a leafminer, the larvae of a tiny insect that "mines" inside the leaves. You may prefer not to treat with a systemic insecticide since you're going to be eating the tomatoes (a systemic insecticide is taken up by the plants so that the insects inside the leaves are exposed to it). A contact (exterior spray only) will not control them because they are protected by the skin of the leaf. You can pick off and destroy the worst affected leaves but supposedly tomatoes can tolerate quite a bit of damage from leafminers.
