You know how much we love trees, but did you know that insects love them too? Many of the insects that you find in your garden are ‘beneficial insects’ that support healthy plant growth. In this article, we take a look at New Zealand’s most common beneficial insects, and how you can attract them to your garden.
Beneficial insects fall into two categories: pollinators and predators.
Pollinators help your garden grow by transporting pollen from one plant to another, enabling fertilisation and seed production. Pollinators are great for every garden, but especially important if you grow veggies that need pollination (like potatoes, broccoli, tomatoes, and cucumbers) or if you have fruit trees.
Predators are your garden’s natural pest control squad, keeping aphids, thrips and other plant-damaging insects under control. A low pest population makes it much easier to keep your garden healthy - and when beneficial insects are doing most of the work, you can cut back on your pesticide use.
Don’t be fooled by their cute appearance, ladybirds are one of the most impressive predators in your garden. An adult ladybug can eat 100 aphids a day, and they also take care of thrips, mites, mealy bugs and many other garden pests.
Attract ladybirds to your garden with plants like fennel, dill, and parsley. They also like carrots that have gone to seed; it’s worth sacrificing a carrot or two to have your own aphid management team on standby!
Honey bees and bumblebees are the hardest-working pollinators in the garden. To get your garden buzzing, plant plenty of flowers, flowering shrubs or climbers (like wisteria, lavender and hebe), and native flowering trees like pohutukawa and mānuka.
Bees are especially fond of flowers with flat, open shapes - it’s easier for them to get to the nectar - but will be attracted to most flowering plants.
Spiders might not be everyone’s favourite creature, but they’re certainly handy to have around. Garden spiders get rid of slugs, mites, aphids and small larvae. They like mulch and leaf litter, so when you’re providing food for your trees, you’re also making your garden spiders feel at home.
Daddy-long-legs (harvestmen) are also very beneficial. They eat small slugs and other insects, as well as decomposing plant matter, fungi, and even bird droppings… they aren’t picky.
Their varied diet means that unlike many insects, which leave the garden in winter when food supplies are low, harvestmen will stay in your garden all year round. This means that when the pests come back in spring, the harvestmen are waiting to meet them.
Hoverflies help with both pollination and predation; adult hoverflies are excellent pollinators, and hoverfly larvae can keep your aphid population under control. Hoverflies can control up to 80% of an aphid infestation!
Praying mantises are stealthy predators with enormous appetites. As well as aphids and mosquitoes, mantises will eat cabbage white butterfly caterpillars, protecting your brassicas.
