I’d say most people have little regard for pollinators at all. They might even think the world would be better if all these critters went extinct. Bees, wasps, beetles and the like are usually not among your average person’s list of favorite organisms.
These disparaged creatures are vital to our food supply. Our environment would be drastically different without them. Most plants need to be pollinated to reproduce, and there are three ways this is accomplished.
Some plants self-pollinate, and this can usually be accomplished without any outside interference. Flowers that have male and female parts near each other are often good candidates for self-pollination. In vegetable gardens, prime examples are: tomatoes, peppers, peas and beans. You might see bees working them, but pollinators aren’t necessary.
Fruit trees and most blueberries are an exception. They have stamens and pistils near each other, but these plants will not self-pollinate. That’s why two different cultivars must be planted or be close enough to another of the same species for pollinators to transfer pollen.
Another way plants may be pollinated is by wind. Corn is a good example here. Pollen travels from the tassel of one plant to the silks of the same or a different corn plant through a combination of wind and gravity. That’s why in small plots like home gardens it’s best to plant corn in blocks rather than in a few long rows.
The final way plants are pollinated is by insects, birds, bats or the like. These creatures visit the flowers and physically spread the male gamete to the female gamete. This is not their goal. They aren’t altruistic creatures, but their actions result in fertilization and seed production.
Some plants have what we call imperfect flowers. Flowers of this type are either male or female. Those plants not fertilized by wind are dependent on pollinators. Garden examples are: cucumbers, squash, pumpkins, watermelons and cantaloupes.
Asparagus, hollies and persimmons are examples of plants that are totally male or female. Both sexes of plants must be present for fruit to develop. In other words, your holly bushes will never set fruit unless both male and female plants are nearby. Once the flowers wither, your shrubs will remain green the rest of the season. The same goes for your persimmon tree.
This whole process is important to more than our gardens. The whole ecosystem would be drastically changed if we didn’t have species that depended on nectar and pollen as their primary or total food source.
Pesticide safety is critical. We must be careful to target our chemicals, so we limit their exposure to beneficial insects and other pollinators. Spraying when these critters are active should be avoided, if possible. For home gardeners, it’s often helpful to try other methods of pest control.
When selecting plants for your garden or landscaping, always keep in mind the pollination requirements. You could do everything else correctly and still not get the results you want. Also, if you don’t want to encourage bees, beetles or wasps, select plants that don’t require pollinators.
Ted Manzer teaches agriculture at Northeastern High School.
I am not certain what to think about this current fad of planting for pollinators. I remember how ‘environmentalists’ wanted to protect blue gum and red gum eucalypti outside of Los Osos because the monarch butterflies swarmed onto them for nectar. They think that the (exotic) trees benefit the butterflies. The problem is that plant specie that rely on the monarch butterflies for pollination were being neglected One can not help but wonder if that is (part) of the reason for the decline of the California poppy.
I agree with your logic. Stay tuned for next week’s column about native pollinators, native plants and the problems when we try to cut corners with exotics.
Oh no! I just wrote something brief to that effect, and am worried about the response. It is for the gardening column, so is very brief. It will offend some nonetheless.