They take a L-O-N-G time to go from germination to fruit. We usually start our tomato seeds in a greenhouse around the first of March in order to have them ready to transplant to the outdoors by the 15th of May. Given that’s only a month away, you may do better to wait until about then, and start off with transplants where the tomato plant is already a strong 12″ – 24″ tall, and ready to go in the ground. Find out your area’s last frost date, then figure you’ll plant around then with a living tomato plant that already has a good start. Also be prepared to over it, in case you get some frosty nights after that. That’ll get you well on your way to having tomatoes this summer.