A hybrid plant is the result of cross-pollinating two different plant varieties and growing the seed the cross produces. The plant that grows from that seed is considered a hybrid.
Why Hybridize Plants?
Commercial hybridizing is a process by which new, marketable plants are developed with particularly desirable qualities. Hybrids are developed for disease resistance, size of plant, flower, or fruit, increased flowering, color, taste, or any reason a plant might be considered special. Most modern plants currently available to home gardeners are hybrids.
How Plants Are Hybridized
To create a hybrid, pollen from one variety of plant is transferred to the flower of another variety. Before doing so, the breeder has to decide which plant to use as the female (the pistil) and which he wants to take pollen from (the stamen, male parts). The pistil is pollinated manually. To prevent the plants from self-pollinating, all the stamens have to be removed from the plants that are going to pollinate. The fruits that form as a result of this cross-pollination are harvested and the seeds are collected.
Getting to the desired result can take years of cross-pollination. First-time crosses are grown out the following year and the plants they produce are evaluated. If they meet expectations, the cross will be repeated and the seeds will be marketed the following year. But it can take many years before a hybrid with the desired traits is even created. If the resulting plants are disappointing, the breeder is back to square one.
Even when the breeder has a winner, the process continues. Seeds for popular commercial hybrids, like Sungold and Early Girl tomatoes, have to be crossed, harvested, and saved every year. These are called F1 hybrids, for first generation, because they are the direct product of a cross. The breeder who first creates a hybrid owns the rights to it, which is why they can be more expensive than non-hybrid (open pollinated) plants. Breeders guard the parentage of their hybrids closely.
Success growing hybrid plants in the garden is no more difficult than growing non-hybrids (open-pollinated plants). In fact, many of the most popular varieties of garden plants are hybrids because they have proven to be top performers in the garden.
Meyer lemon trees are a hybrid plant created by crossing a regular lemon tree with a mandarin orange tree. A favorite amongst chefs, the resulting fruit is sweeter, the flesh is dark yellow, and the skin is thin and smooth.
What Happens When You Plant Seed From Hybrid Plants?
Because hybrids are a cross between varieties, the seed produced by hybrids will not grow true to seed. Seedlings grown from a hybrid could exhibit traits of one or both parent plants or be something totally surprising. Sometimes the seed is sterile and does not grow at all.
This doesn't mean you can't save and experiment. You could be totally delighted with the new plants. Just don't get attached to them, because you may never see plants like that again.
Once a Hybrid, Always a Hybrid?
It is possible for the hybrid seed to be stabilized and become an open pollinated plant so that it continually grows true to type. The process involves growing out several generations of seed, carefully selecting only those that are identical to the parents and discarding the rest. However many non-hybrid seeds are a result of this painstaking process.
Are Hybrid Plants Unnatural?
Most hybrid plants are intentional crosses, but hybridization can occur in nature. In fact, it happens quite often. Two nearby plants of different species can be cross-pollinated by insects or the wind and the resulting seed simply falls on the soil and grows into a hybrid. Few of the flowers and vegetables we grow today are in their original wild form. In nature, hybrids are hit or miss. Commercial hybrids come about after a great deal of work and many attempts are discarded if they do not produce the desired results.
Whether the cross occurs naturally or intentionally, do not confuse hybrids with genetically modified plants (GMO), which are created using techniques such as gene cloning. Hybrids are simply two plants that cross-pollinated.