It depends on where you live and whether or not your area has received its last frost. I live in northern California and will be waiting until the end of March to plant tomatoes. I could start them indoors now and then plant them outside later, but I prefer to start everything in the area they are slated to grow. So, the soil has to be the right temperature before I plant it (about 45-50 degrees). Tomatoes are the first things I plant. I have a salad garden, so most of the things I grow like the same condition as tomatoes. I'm thinking of planting lettuce, peppers, onions, and other things I like to put in my salad.