Since tomatoes are America's favorite garden vegetable, it's no surprise that there are hundreds of varieties to choose from. Home garden tomatoes range from bite-size currant, cherry, and grape tomatoes to huge beefsteak fruits, in nearly every color except blue. You can grow tomatoe varieties that produce fruit extra early, and there are varieties for every type of climate, including many that are resistant to one or more common tomato diseases. Don't forget tomatoes especially developed for slicing, canning, juicing, or stuffing, too.
Discovering which tomato varieties are best for your garden will involve some experimenting, and your climate and personal taste will play a role, too. Some early types such as 'New Girl' and 'First Lady II' will be ready to pick about two months after you set plants in your garden, while main-season hybrid and heirloom varieties can take up to 80 days. To extend your harvesting season, be sure to plant some of each type.
Tomato plants are vines, and they have two basic ways of growing, called determinate and indeterminate. The vines of determinate varieties (sometimes called bush tomatoes) grow only 1 to 3 feet long, and the main stem and side stems produce about three flower clusters each. Once flowers form at the vine tips, the plant stops growing. This means determinate types set fruit over about a two-week period and then stop, which makes them excellent choices for canning. Indeterminate tomatoes have sprawling vines that grow 6 to 20 feet long. Most produce about three flower clusters at every second leaf. They keep growing and producing unless stopped by frost, disease, or lack of nutrients, which means you can keep picking fresh tomatoes the whole season. Pruning is necessary, however, or they will put too much energy into vine production.
Nurseries and garden centers offer a wide range of dependable, disease-resistant varieties such as 'Jet Star', 'Celebrity', and 'Sweet 100', and many sell transplants of popular heirloom tomatoes such as 'Brandywine', 'Green Zebra', and 'Cherokee Purple' as well. But if you want to take advantage of the full range of available cultivars, you'll have to grow tomatoes from seed. Unless you plan to preserve a lot of your crop, 3 to 5 plants per person is usually adequate. Unused seeds are good for 3 years. Specialty mail-order suppliers also offer individual tomato plants for sale, which could be a good option if you don't have space for growing your own from seed.
At 6 to 8 weeks before the average last frost, sow seeds ¼ inch deep and 1 inch apart in well-drained flats. Seeds will germinate in about 1 week when the soil temperature is 75° to 85°F; at 60°F the germination process can take 2 weeks.
In most places, a sunny spot indoors, such as a south-facing window, provides the warm, humid environment young seedlings need. If you don't have sunny windows, use a heating coil for bottom heat and a fluorescent or grow light overhead. Lack of adequate light will make seedlings leggy and weak.
Once the seedlings emerge, keep the temperature no higher than 70°F, and water regularly. Once a week, feed with compost tea or fish emulsion, and discard any weak or sick-looking seedlings. When the second set of leaves—the first true leaves—appear, transplant to individual pots or deep containers (such as plastic cups), burying the stems deeper than they stood previously. Whatever container you use, make sure it has drainage holes in the bottom. After this initial transplanting, give the seedlings less water and more sun. As the weather warms, harden off the plants before planting them in the garden. Again, discard any weaklings that might harbor disease.