Build a circle of life in your garden with an insect ecosystem for free pollination, natural pest control and food for animals and birds.
Did you know that insects are among the most successful creatures on Earth?
Over a million species of insects have been identified, but scientists believe a significant number has yet to be named. The beetle order is the largest in the insect class. Insectopedia (Struik Nature, 2017), a book by Dr Erik Holm, an emeritus professor and a former head of entomology at the University of Pretoria, uncovers the secret world of southern African insects.
The book explores the intriguing behaviour and biology of insects, from mating and breeding, metamorphosis and movement to sight, smell, hearing and their adaptations to heat and cold.
Previously published as Insectlopedia of Southern Africa (Lapa), the book has been extensively revised and redesigned, and includes up-to date information, an expanded identity section, many new photos and an illustrated field guide that describes most insect orders and their main families.
Insects in our gardens Insects are an integral part of any garden ecosystem. Insects in the garden fall into two distinct categories – the good guests we want to encourage to visit and the bad guys who leave a path of destruction.
Beneficial insects, like bees and butterflies, are important for pollination. Predatory insects feed on unwanted insects, keeping populations in check. The bad guys either chew holes in plants and damage leaves, fruit and flowers or destroy plants by sucking out the sap in stems and leaves.
Insects are also a good food source for animals and birds “A garden should be seen as one’s own private nature reserve, especially when planted with predominately indigenous plants,” says Holm.
“This is, in fact, one of the aims of my book – to encourage people to discover the treasure trove of a garden populated with indigenous insects and share the experience with their children.”
Holm says the honeybee is the most beneficial insect to gardeners.
“It pollinates a wide variety of flowering plants, particularly perennial herbs like lavender and basil.
Bees pollinate over 80% of all flowering plants, and they themselves provide food for many birds, spiders, praying mantises and others.” Holm adds ants are often overlooked as beneficial insects to have in the garden.
“Kept off the plants and on the soil with ant barriers, they act as important controllers of other insects and their eggs. Their tunnels aerate the soil, improving water penetration and fertilisation.”
Natural pest control
Encourage beneficial insects to reside in your garden by setting up an insect hotel. What started out as a practical way to get bring insects back to city gardens is now a fabulous fashion statement and popular focal point in gardens throughout the world. Before reaching for chemical pesticides to control unwanted bugs in your garden, choose eco-friendly, organic insecticides or make your own, and use companion planting methods for your garden. This will help to restore balance to the ecosystem and save beneficial insects that are also destroyed by chemical insecticides. Predator insects, animals and birds provide free pest control. Attract insect-eating birds to your garden by including plants that attract insects. Fallen logs and a thick layer of mulch also provide a place for insects to breed and will attract those birds that forage close to or on the ground.
Good guys and bad guys
What beneficial insects and which pests should you be on the lookout for in your garden?
● Bees are vital for pollination. Encourage them by planting yellow, white, purple and blue flowering plants in your garden.
● Lady beetles, or ladybirds as they are colloquially called, prey on aphids. One ladybird can eat about 50 to 60 aphids a day.
● Praying mantises will prey on a number of beetles, caterpillars and moths, as well as grasshoppers and mosquitoes.
● Lacewing larvae are ferocious aphid eaters and will also eat the eggs and larvae of other insects. Adult lacewings are preyed on by frogs, lizards and spiders.
● Damselflies and dragonflies feed on mosquitoes and many other small insects.
● The assassin bug kills many garden pests but may also feast on beneficial insects. Take care, its bite is nasty!
● Cutworm are larvae of various species of night-flying moths. They destroy seedlings by biting into the stems at ground level. Bait cutworm by placing small piles of oats mixed with sugar and a little water close to newly planted seedlings. Check the traps at night and remove the cutworms.
● The yellow-and-black amaryllis caterpillar, or lily borer, will tunnel into nerine, clivia and amaryllis and, if left unchecked, they will bore through the bulb and kill the plant. Use Margaret Roberts Biological Caterpillar insecticide to control them. The product is harmless to other insects.