Читать книгу The Wildlife-friendly Garden - Michael Chinery - Страница 15

Adjusting the way you grow things, or even what you grow, can make your garden less attractive to pests. Most weeds, for example, can be eliminated by spreading a layer of chipped bark or compost over the garden. You can try growing red cabbage instead of the traditional green varieties: this may not deter the cabbage white caterpillars, but at least you can see them more easily and remove them before they do the damage!

Companion planting or inter-planting is often used to reduce damage by pests. Planting onions and carrots close together works well because the smell of the carrots deters or confuses the damaging onion-fly, and the smell of the onions discourages the carrot-fly. Roses or other flowers planted at the ends of vegetable rows attract hover-flies, which may lay eggs on aphid-infested crops. Some hover-fly larvae can demolish the aphids at a rate of one every minute!

Doing nothing and allowing nature’s web to keep the pests in check is probably the best method of all. Surely losing a few plants to beetles and caterpillars is a price well worth paying for a garden which is teeming with wildlife and with no risk of poisoning yourself or your family?

BIOLOGICAL CONTROL

Biological control, which uses natural enemies to keep pests in check, can be wonderfully effective. Introducing ladybirds and their larvae to your garden, for example, can wipe out an infestation of aphids in days. A single ladybird larva may eat 500 aphids in its three-week development. Green lacewings (see here for stockists) do a good job on summer populations of aphids, and are useful in greenhouses throughout the year.

Biological control of slugs, which are surely at the top of most gardeners’ hit-lists, can now be achieved simply by using a minute parasitic worm called Plasmarhabditis hermaphrodita. Available through good garden centres and other suppliers (see here), the worms seek out slugs and bore their way in. They multiply rapidly and the slugs literally explode, releasing another generation of worms to carry on the work. It is unlikely that the worms will move out into surrounding areas in the numbers required for slug control, so the hedgehog population will not go hungry.

Snails can be kept in check by song thrushes as long as you have sufficient anvils on which the birds can break the shells. If you have no concrete paths or rockery stones, lay a few bricks or large stones around the garden and listen for the tapping as the birds get to work.

Colin Varndell

Song thrush

Michael Chinery

Roses are often planted in vineyards. Hover-flies, which are attracted to the flowers, lay their eggs on the surrounding vines, where their grubs attack harmful aphids and other pests.