Get the natural gardening bug – literally
There’s a growing trend towards living more sustainably, whether it’s in the way we build our homes, the type of cars we drive (or don’t) and growing our own food.
For some people, gardening segues into a desire to grow their food as organically as possible. Fortunately, Mother Nature has provided an army of critters that can do battle with garden pests on a massive scale. And while there are ways to attract beneficial insects into the garden to feast on aphids, mites, caterpillars and other plant-consuming bugs, those of us who tend to be a little more impatient can have battalions of insects winging their way to our door with the click of a mouse button.
There are four categories of beneficial insects:
These are generally larger than their prey and consume many pest insects throughout their lifetime. They are often considered general feeders, which means that they eat a variety of insect species. Unfortunately, some predators, like the voracious praying mantis, will eat just about anything in its path, including other beneficial insects. Both immature and adult predatory insects consume garden pests and some feed on pollen and nectar at various stages of their life-cycle.
These lay their eggs on or inside a host insect or egg. When their eggs hatch, the young larvae consume the host, eventually killing it. Parasitic insects are usually much smaller than their host and tend to be more insect specific than the predators. However, this is not always the case. The tiny trichogramma (wingspan: 1/50th of an inch), is a parasitic wasp that attacks the eggs of at least 200 different moth and butterfly species preventing the leaf-eating caterpillar from emerging (think cabbage loopers and corn earworms).
These help keep plant species growing and producing year after year. As much as 80 per cent of the world’s flowering plants require pollination to produce fruits and seeds — including two thirds of all food plants. Honey bees, butterflies, beetles, flies, and wasps are all well-known pollinators. A lesser known beneficial insect, the hover fly, not only pollinates plants in its adult stage, but feeds on soft bodied pests, like aphids, in its larval stage.
TIP: Use short-lived organic sprays only as a last resort to reduce the risk of harming pollinating insects. If they’re gone, all of your best efforts spent fertilizing, pruning, watering and weeding will be wasted. Encourage or import pollinators whenever possible.
These guys are essential for breaking down garden waste and enriching the soil by releasing nutrients into a form that is usable by plants. They include a diverse group of soil-dwelling and wood-boring insects and are largely responsible for creating the rich, dark organic layer of soil (humus) that blankets a portion of the earth. Without these insects we would be “neck-deep” in excrement and dead plant and animal tissue. (Three cheers for the decomposers!).
Who’s who in the insect army
Ladybugs: Beautiful and deadly, this is one of the best-known garden predators.
Praying mantis: These are shipped as egg cases and need several weeks of warm temperatures to hatch.
Aphid predators: They are attracted by the smell of honeydew and attack pest colonies.
Fly parasites: As the name suggests, these small non-stinging wasps kill ilth flies.
Fungus gnat predator: They search for fungus gnat larvae and other soil pests.
Green lacewig: These voracious predators can eat up to 60 aphids an hour.
Aphid lion: Feeds on most soft-bodied pests.
Leafminer parasite: Attacks larvae in the mine.
Mealybug destroyer: Eats all mealybugs as well as aphids and soft scale.
Pirate bugs: Arrr! They destroy thrips, spider mites and more.
Predatory mites: An effective control for use against two spotted spider mite.
Whitefly parasites: An aggressive non-stinging wasp that controls greenhouse whiteflies.
Make your friends welcome
Whether you choose to attract or buy good bugs, you’ll need to provide an attractive home, or they won’t stick around.
Choose plants that provide plenty of food. In general, insects will eat pollen and nectar from plants with small flowers. Attractive annuals and perennials can be sown throughout vegetable rows or planted as a border around the garden. Be sure there are both early and late bloomers in your seed mix so the insects have enough food when pest number die down.
Include plants of different height. Low growing plants, such as mint, clover and thyme, act as a shelter for ground beetles, while fruit trees and many flowering shrubs create a safe habitat for parasitic wasps and other flying insects. Leaf litter, mulch, and ground debris provides protection from birds as well as offering shelter from the elements.
A shallow birdbath or dish filled with small stones will supply plenty of water for tiny bugs. Insects can also drink from the wet leaves and puddles created by overhead sprinklers.
Many thanks to the team at Planet Natural for their help in preparing this article.