Hundreds of tomato varieties exist, but tracking down an old favorite can be challenging. Most of the tomato plants sold at garden stores or nurseries are hybrids--plants bred for vigor and disease resistance. These tomatoes are reliable producers and popular with gardeners. They can seem rather dull, though, and lack the robust flavor of heirloom tomatoes. If you're dreaming of your grandmother's tomatoes or want to try one of the gold, purple or striped varieties, look beyond your local garden store. For the largest variety, grow tomatoes from seed.
Consult a local county extension office to find tomato varieties suitable to your area. Gardeners in high-altitude areas or areas with a short growing season should select high-altitude adapted tomatoes or fast-maturing varieties.
Search local nurseries for the tomato varieties of your choice. Nurseries may special order plants for you or provide a similar variety.
Consult online seed catalogs. Many tomato varieties are available as seed, but not as plants. For rare or heirloom seeds, contact a seed exchange.
Visit small, organic farms. These farms often experiment with heirloom varieties and may be willing to sell you unusual tomato plants. Vendors at farmers markets often sell heirloom tomatoes and may sell you plants or provide you with a source.