It’s a bug-eat-bug world in the garden

 In Opinion

by Cathy Krar, Master Gardener

The truth is that most insects are not harmful to us or our gardens. If we put more effort into learning to recognize pest-eating helpful insects, it would reduce our reliance on pesticides and naturally keep control of predators who consume our beloved plants.

Companion planting can be useful in providing food sources that attract and support insect populations; and create a natural balance in growing plants together that can be mutually beneficial. Planting a vegetable garden with plants that repel pests can increase yields, reduce disease, and limit the insects that ravage crops.

Flowering herbs like oregano and thyme are a magnet for pollinators like butterflies, hummingbirds, and other insect allies who protect our gardens. Don’t use pesticides! They kill the good guys as well as the bad. It is the hoverflies, praying mantes, lacewings,ladybugs, parasitoid wasps, tachinid flies, wolf spiders, and ground beetles that do all the hard work.

Be observant. Get to know what the larvae of your friendly insects look like. Plant “flowery friends” in the garden. A suggested practice is to plant: a vegetable, an herb, and a flower in proximity.

Parsley is a great friend of asparagus and peppers. It masks the odour of the host-seeking aphids and asparagus beetle. Not only that, but it also attracts wasps and tachinid flies. Since asparagus is an early crop, planting lower growing parsley is an effective way to use that space underneath.

A big-time tiny helper in your garden is the tachinid fly. Tachinid flies lay their eggs in the caterpillar of cabbage worms, spongy moth (Lymantria dispar dispar), Colorado potato beetles, corn ear worms, cucumber beetles, cutworms, earwigs, Japanese beetles, bean Beetles, sawfly larvae, squash bugs and tobacco budworms. Give yourself a high five, if you have these mighty helpers in your garden!

The combination of calendula and broccoli is successful because the flowers create a sticky substance that attract aphids and traps them there. As a bonus, ladybugs stop by to eat the aphids. A win-win.

Parsnips and carrots planted with onion, garlic, or leeks are said to ward off carrot root flies; and the smell of carrots or parsnips deters leek moths. Another mutually friendly relationship.

Lavender will attract many pollinators, and when planted near tomatoes and beans will increase the bee, butterfly, and hoverfly populations. As an added benefit, lavender further discourages pests from carrots and leeks.

Mint confuses flea beetles that enjoy laying their eggs on brassicas. A word of caution, mints are vigorous growers, so better to place them in pots in the garden. Sage (Salvia officinalis) also has a strong enough scent to confuse black flea beetles and cabbage moths from brassicas, as well as carrot flies from carrots.

The planting of wormwood (Artemisia absinthium) is a balm to pollinators. It keeps blackfly aphids from bean crops. Even ants, slugs, snails, mice, deer, and rabbits will avoid its strong odour and harsh taste.

A great combination to plant with lettuce is chives or garlic. Aphids don’t like the smell and if you plant alyssum nearby, it will attract hoverflies and lacewings to snack on a meal of aphids.

Consider this: Don’t underestimate “flower power” in vegetable gardens. Consider planting flowers like cosmos, lobelias, marigolds, tansies, rudbeckias, scabiosas, yarrows and zinnias that work with Mother Nature to attract beneficial insects and pollinators. We can all encourage the good bugs to stick around by offering a habitat for them to thrive.

This series of gardening articles brought to you by the Simcoe County Master Gardeners, members of the Master Gardeners of Ontario. For more information, visit www.

Whitney Cranshaw photo/Savvy Gardening: Feather legged tachinid fly harlequin bug

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