You should Plant a variety of flowers to help encourage insects into the garden. We all know how important companion planting is in the vegetable garden. Many predators and parasites feed on pollen and nectar or use flowers to supplement their food supply if they run low on pests. Plants in the carrot family and mustard family are especially attractive to beneficial insects. Use plenty of plants with small flowers such as sweet alyssum, dill, fennel, garlic chives, lovage, coriander and white lace flower (A cultivated version of Queen Anne's Lace). Other popular plants for beneficial insects include: French marigolds, coneflower, coreopsis, cosmos, tansy, yarrow, goldenrod, sunflowers, yellow alyssum, sweet clover, buckwheat or hairy vetch. Let a few of the broccoli plants flower, the yellow flowers are irresistible.
One of the best ways I think to control common pests in your garden is to support their natural enemies. Planting pollen and nectar rich plants, and providing protection for these beneficial insects, is a basic principle of organic gardening, and a way to further increase the ecological diversity of your yard. I have listed the most common beneficial insects along with tips on attracting them to your Garden.
The familiar round, orange spotted ladybug is just one of more than 400 species of lady beetles found in Europe and North America. Most ladybird adults and larvae feed on aphids and other soft-bodied insects. Adults are attracted to flower nectar and pollen, which they must eat before they are able to reproduce.
Pale green or brown lacewing adults have distinctive large, veined wings and feed mainly on flower nectar. Lacewing larvae, however, are voracious predators that feed on aphids, thrips, scales, moth eggs, small caterpillars and mites.
The adults look like small bees with striped abdomens; the grayish or greenish slug- like larvae have pointed heads. Flower flies are attracted to flowers to feed on nectar and pollen. The larvae feed on aphids in tight places where other good bugs can't go, and are especially helpful in early spring, before other beneficial insects are active. Flower flies also pollinate strawberries and raspberries, producing larger fruits and higher yields.
Large, long-legged, shiny blue-black or brown beetles that hide under rocks and logs during the day, and are fast-moving when disturbed. They feed on slugs, snails, cutworms, root maggots. Attract them by providing perennial ground covers, stones, or logs.
Hunting and parasitic wasps:
(These are more suited to greenhouse conditions here in Ireland) There are hundreds of species of wasps, including many that are so tiny you can barely see them. The one most people are familiar with is the encarsia formosa. These mini-wasps often attack the eggs of pests, and are one of the most important insect groups that provide control of garden pests. They can be attracted by growing by pollen and nectar plants.
All spiders feed on insects and are very important in preventing pest outbreaks. The spiders normally found in gardens do not move indoors, nor are they poisonous. Permanent perennial plantings and straw mulches will provide shelter and dramatically increase spider populations in vegetable gardens.
(the pictures were downloaded from the web) Andy