Pollination is completely natural. But what do we know about it? Here is a summary of what you need to know!
Pollination is the transfer of pollen from the stamens (male reproductive organs) to the pistil (female reproductive organ) of a plant. It ensures fertilization and the production of seeds and fruits.
Pollen is usually transported from flower to flower in one of two ways. By wind, usually in plants that flower inconspicuously, such as large trees (pines, birches, etc.) and some other plants, such as grains and the infamous ragweed. Or by animals, mostly by insects (bees, butterflies, hoverflies and many others), but also by hummingbirds. The plant then produces showy or fragrant flowers to attract the pollinator and often offers nectar and some pollen as a reward. As the animal moves from flower to flower to feed, it picks up pollen as it passes and deposits it on the next flower. Thus, fertilization takes place and the seeds or fruits follow.
Importance of pollination for the gardener
Pollination has little influence on the gardener if he only wants beautiful flowers to admire and plants with edible leaves or roots to eat. But if he wants fruit or seeds to eat – or seeds to sow for the next year – pollination is very important. Without it, there is no fertilization, so no fruit or seeds.
Some plants can self-pollinate: a supply of their own pollen can ensure fertilization. But for others, the pollen must absolutely come from another plant of the same species. For many fruit trees in particular, another cultivar is needed nearby to ensure fertilization and thus fruit production. It is a protection of Mother Nature against inbreeding! This is the case for apple trees, camerisiers and most pear, cherry and plum trees, for example, but even theoretically self-compatible small fruits produce better when there is a pollen exchange with another variety.
So when planting a fruit tree, always consider planting two different varieties of the same species. And encourage pollination by growing plenty of flowers to attract pollinators.
Most flowers are called “perfect”: they are both male and female. But for some plants, there are both male and female flowers, either on the same plant or on two different plants. Holly and kiwi, for example, are either male or female; be sure to plant at least one male for every eight females.
In cucurbits (squash, cucumbers, melons, etc.), the same plant produces flowers of both sexes (more males than females), but an insect must visit the flowers and carry the pollen. If it is cold, very hot, raining or if there are no pollinating insects in the area (perhaps as a result of insecticide treatments), the gardener must “do the bee”.
How to pollinate your flowers yourself
Simply insert a small brush or cotton swab into a male flower (easy to recognize, as it has no ovary at the base) to collect yellow pollen, then push it into the center of a female flower (it will have an ovary at the base), thus touching the stigma.
In tomatoes, self-pollination is possible, but the flower still needs to be shaken to drop the pollen onto the pistil. Without a drone to vibrate the flower, or at least wind, there will be no fruit. And the situation is worse when it is very hot, because the pollen is then not very sticky and it takes several visits to ensure fertilization.
The more pollen that lands on the flower pistil, the bigger and better shaped the fruit will be. Therefore, many gardeners no longer rely on insects, but still make the bee to ensure a beautiful and abundant harvest!