Cross pollination occurs when a plant’s pollen is carried to the other plant’s female reproductive part, known as the stigma. If the two plants are compatible, this exchange offers the benefit of a varied gene pool and carrying on the traits of the parent plants. Genetic variation is essential in plants (and animals) to help ensure survival in case a pest or disease becomes widespread among the population. Another benefit of cross-pollination is the potential for hybridization. Hybrids can form new species from their seeds or be sterile and not perpetuate at all.
A widespread concern amongst gardeners is if their plants will cross pollinate and how it will affect their fruits. Can tomatoes cross-pollinate with peppers to form a tomato-pepper hybrid?
Tomatoes and peppers are not genetically compatible plants and cannot effectively hybridize. Despite both tomatoes and peppers being in the same family, Solanaceae, this does not make them effective cross-pollination candidates because of their genetic differences. Other plants in this family include bell peppers, eggplants, and potatoes, but none of these plants can cross-pollinate across species lines.
Continue reading to learn more about how cross-pollination occurs, what plants can effectively cross-pollinate, and how you can avoid cross-pollination.
How does cross-pollination occur?
Cross-pollination occurs naturally from pollinators such as bees, butterflies, and birds collecting pollen from one plant and then transferring it to another, usually during the process of collecting nectar. Certain plants such as oats or pistachio trees also can be wind-pollinated, which adds another element of unpredictability.
Humans can hand-pollinate plants that do not have natural pollinators or attempt to create a hybrid. To be a viable, stable hybrid, the two “parent” plants must have compatible genetic factors to make this possible, such as chromosome number and bloom time.
The resulting seeds will be the hybrid seeds, while the fruits on the mother plant will remain unaffected. This is because the genetic information used to create the fruit is already present in the plant. Unstable hybrids can form between plants with different numbers of chromosomes, but these likely will not survive and often do not produce fruit.
A common myth some gardeners might fall prey to is believing that two similar plants that are planted next to each other will cross-pollinate and ruin their intended crops, such as a strange yellow squash and cucumber hybrid.
This is impossible because the pollen present from the other plant does not dictate how the mother plant grows its fruit. However, the seeds present in the fruit may hold a mix of genetic information from the mother plant and the plant that provided the pollen. The seeds would have to be planted and then the fruits harvested to tell what impact the cross-pollination had.
What can you cross-pollinate with peppers?
While peppers typically do not need external pollen from another plant because they are self-fertilizing, hot peppers and sweet peppers are genetically compatible and can cross-pollinate with each other. This cross would form seeds in the plant with the genetic information of both hot and sweet peppers.
The resulting fruit could be hot or sweet if these seeds were to be planted. Peppers can be crossed with other peppers successfully, but the thing to remember is the fruit on the mother plant will not be affected; only the seeds from the cross-pollinated plant will result in a hybrid fruit.
Essentially, all members of the Capsicum genus can cross-pollinate with each other, with one exception of Capsicum pubescens. This species is genetically different enough compared to the other species in its genus, where it could not form a successful hybrid.
What fruits will cross-pollinate with each other?
Compatible plants will readily cross-pollinate with each other if given close enough proximity and pollinators that visit both types of plants.
Examples of cross-pollinate plants are in the Brassicaceae family, commonly known as the mustard family. Kale, broccoli, cauliflower, and brussels sprouts are all the same species, Brassica oleracea, that have been selected for different traits.
Therefore, these can all cross-pollinate with each other. Tomato varieties can create natural hybrids as well, and their seeds can be planted to see what the hybrid grows into and what characteristics were passed to the fruit.
Much like peppers, fruits in the same genus will likely be able to cross-pollinate without any issues. Citrus fruits are commonly hybridized to create more desirable fruits and are then selectively bred to create popular fruits such as Meyer lemons, which are a cross between mandarin oranges and lemons.
How can cross-pollination be avoided?
Cross-pollination can only be avoided for sure if a single variety is grown in a sealed-off greenhouse. Since cross-pollination is a natural occurrence, and it is tough to stop pollinators from doing what they must to survive, there is always a chance that like-crops will be cross-pollinated.
On an industrial scale, crops may be able to be planted with enough distance (at least 300 feet) apart and with a “buffer crop” between to avoid potential cross-pollination.
Still, the way to be most certain there is no risk of crosses occurring is by having an enclosed, isolated environment for each specific crop. Mesh bags can also be used to cover the flowers and stop pollination from occurring entirely, which may be more beneficial to the home gardener who can do this on a smaller scale.
While cross-pollination has many myths, the basics are that the two plants must be compatible to cross-pollinate and create viable hybrids effectively. The immediate plant will not be affected, only the seeds borne from the fruit of the plant that has been cross-pollinated.
Plants in the same family are often genetically different enough to where this would not affect the plants. In contrast, plants in the same genus or species, such as hot peppers and sweet peppers, can mix genetic information to create a new hybrid or even a new species.
To avoid cross-pollination, a few methods can be implemented depending on how adamant the gardener is about preventing the possibility of it occurring.
Overall, pollination and cross-pollination is a natural occurrence and is necessary for speciation to occur and necessary to create strong, healthy plants that will persist well into the future without the need for human intervention. Without pollinators, the world’s food supply would look drastically different and lack much of the diversity we are used to seeing.
Hi there, my name is Allie and welcome to my blog; GareningWithAllie!
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