The benefits of planting for pollinators
Last month, I announced a Garden Contest, inviting you to tell me what you are doing in your own gardens to provide food and habitat for our pollinator species. As expected, I received some wonderful entries and I look forward in the next several weeks to visiting the top three gardens and sharing them with you. What impressed me overall with the entries was the level of concern for pollinators that was expressed, the scope of knowledge and awareness, interest in the insects themselves, and a sense of wanting to inform and educate others. As always, I appreciate that people are willing to share their gardens with me; I learn new things and I end up feeling inspired.
That was pretty much what I expected, but as the entries came in, something happened that I hadn’t anticipated: I found that I was paying more attention to the insects that were visiting the plants in my own garden. There were, of course, the usual hon- eybees and bumblebees, as well as iridescent-green sweat bees. In stopping longer to view these easy-to-spot insects, I discovered hover flies, so tiny that it’s easy to miss them. At any time, there might be anywhere from one to a dozen, hovering and maneuvering around the blossoms of the echinacea and the lavender mist flowers.
The body of this diminutive fly is black-and-yellow striped, and at first, I thought they were tiny bees. When I looked at the eyes, however, they were clearly those of a fly. (The insect is so tiny – less than a quarter of an inch – I had to take photos and zoom in on them in order to be able to see this detail.) These are true flies and have no stinger, despite their appearance. The yellow jacket-like coloration is possibly a defense against predators.
Thank goodness for the abundance of information that’s available on the Web. It didn’t take much sleuthing until I stumbled upon a positive I.D. Hover flies (Allograpta oblique) are also known as flower flies, drone flies, and syrphid flies. They make up the insect family Syrphidae.
I learned that, despite their size, these tiny flies can have a huge beneficial impact in the garden. The adults are excellent pollinators – they feed on nectar and pollen – but it goes well beyond that. Information at gardeningknowhow.com told me that hover flies are “nearly as effective as ladybugs and lacewings at controlling aphids. A well-established population of larvae can control 70 to 80 percent of an aphid infestation.” Although they are most efficient at controlling aphids, they also help control other insects, including thrips, scale insects, and caterpillars.”
Hover flies are apparently quite common throughout the United States, especially where there are aphids, so I was surprised that I’d never seen or heard about them before. I certainly am happy that they are present in my garden and on my container plants on the patio.
The main plants that attract hover flies are listed as oregano, garlic chives, sweet alyssum, buckwheat, and bachelor buttons. I have none of these in my gardens this year, so it’s obvious that many other plants attract them as well.
Pam Baxter is an avid organic vegetable gardener who lives in Kimberton. Direct e-mail to pamelacbaxter@gmail.com, or send mail to P.O. Box 80, Kimberton, PA 19442. Share your gardening stories on Facebook at “Chester County Roots.” Pam’s book for children and families: Big Life Lessons from Nature’s Little Secrets is available on Amazon, along with her new companion field journal, Explore Outdoors, at Amazon.com/author/ pamelabaxter.