How to water my tomato plants?

You need two thing to look at. 1, are they drying out from the weather or are the plants using up the water themselves. are they growing fast and have fruit, this will make the plant use more water. If it is possible. Buy a light duty cheap hose and fix it to the pots and up around the hanging plants some how. Zip tie it good and secure. now take a really small straight pin or needle and poke a really small hole in the hose and turn the water on low. as long as you get a little tiny stream coming out you are good. It means more water is going on the plant then what its loosing. You may get some cheap coil hose from the dollar store. Shut it off at night and turn it on in the morning. Have you coffee outside some time and admire what you are growing. that's what so nice about gardening. if you can't do that. then put some wood mulch or a plastic bag over the soil to slow the evaporation rate down. I don't like to much plastic because it will spot the tomatoes bottoms and make them rot.