Summary
Heirloom tomatoes are annual vegetable plants that have not been crossbred, or hybridized, for at least 40 years. They are open-pollinated, meaning the seeds will produce plants identical to the parent plant. This means you can save your heirloom tomato seeds and grow the same tomatoes next year.
Description
Heirloom tomatoes need a bit more care than standard hybrids (which are bred primarily for growing performance rather than flavor), but they tend to have thinner skin, juicier flesh, and better flavor than most hybrid varieties.
Additional Info
Heirlooms, like the many hybrids, are fast-growing, but the plants need 60 to 80 days or more to produce ripe fruit. They are best planted in spring (after the threat of frost has passed) as transplanted seedlings or small plants bought from a garden center.