By Robin Bentley
November 4, 2015
In a garden where the focus is on production I sometimes see the plant’s natural “end stage” as unnecessary. When the parsley, carrots, mint and cilantro, for example, start flowering and setting seed I yank them up to make way for something else. And yet those flowers are important, even in a highly productive p-patch like ours. First of all, there are the bees. Anything we can do to encourage them and reverse colony collapse is crucial. Flowers are also important to a host of other beneficial insects. We hear that term a lot, but what does it mean? Who are they? These “insects with benefits”?
Ladybugs, for one. But you’ve known that since you were three years old. What you may not know is that the predatory larvae of hover flies and parasitic wasps (I know, yuk!) prey on—you guessed it—aphids. So do the aptly-named bright orange aphid midges. With flowers come pollen and nectar—which entices the flying adults of these beneficial insects to stop and raise a family, producing the hungry hordes of predatory larvae which feast on juicy aphids. Yum!
Last summer a lot of our patches were stressed from drought—weakening our veggies and making them that much more susceptible to infestation. Some are tempted in an acute attack such as ours to apply insecticidal soap or neem oil. Proceed with caution, though, as many of the beneficial insects are hidden under the aphids, and they succomb to the soaps and oils as well. My old trick of blasting the aphids with a strong stream from the hose will make the beneficials disappear as well. Even pinching the suckers between your fingers risks killing the good larvae.
So feel good instead about letting some of your plants go to seed—plant a row of alyssum, some clumps of calendula among your veggies, or a border of verbena around the edges…in the case of calendula and many other flowers the petals are edible for humans as well. You can be secure in the knowledge that they’re your best allies in the aphid battle.
As well as eating some of these flowers, the seeds that follow are available for planting next year. So it’s a win-win-win.
In her book, Backyard Bounty Linda Gilkeson lists the following beneficial herbs, flowers and vegetables useful for planting to keep aphids away. She also reminds us to have something in bloom from early spring to late summer by growing a variety of plants. Here are some herbs you probably already have growing somewhere in your patch:
Try letting some of these go to seed, too:
|Calendula||Alyssum||Chinese Greens and Mustards|
|Coreopsis||Basket of Gold (Aurinia)||Kale|
|Feverfew||Daisies||Leeks and Onions|
|Heliotrope||Golden marguerite (Anthemis)|
|From Gilkeson, Backyard Bounty|