Cross-Pollination of Tomatoes

Hybrid Tomatoes

• Hybrid tomatoes are bred to produce consistent size, quality and flavor. Some are bred for ample tomato production or disease resistance. If the flowers can cross-pollinate at all, they still will not produce seeds that will germinate into a plant similar to the parent. It does not matter if two hybrid tomatoes are bred directly with one another, as the resulting seeds will be unpredictable.

Heirloom Tomatoes

• Heirloom tomatoes will produce similar plants in the next generation if they are cross-pollinated with one another. However, heirloom tomatoes lack the uniformity in size and performance boasted by hybrids. Some are quite finicky because they were bred over several generations for traits, such as interesting color or flavor, and not necessarily for ease of growing them. Many heirloom tomatoes are naturally disease resistant, to some degree, because more susceptible plants often died out over the course of cross-pollinating and breeding.

Problems

• Tomatoes can cross-pollinate between many different varieties. If the gardener or a neighbor is growing a different variety of hybrid or heirloom tomato, the tomato plant could be pollinated by a different kind of tomato plant, and the next generation will carry traits from two different parent tomato plants. The results, however, will be unpredictable. Gardeners trying to keep the seed line consistent use wind barriers -- either plants or obstructions such as privacy fences -- and keep different tomato varieties 20 to 25 feet apart in the garden.

Considerations

• Cross-pollination does not affect the tomatoes in the current generation. For example, whether an insect or the wind carries pollen from an identical tomato plant or from a very different tomato plant, the tomatoes that develop from those flowers will look, taste and grow as the genes from the parent plant dictate. The differences do not arise until the seed from the tomato is planted, i.e., the next generation.