How to Create an Insectary Garden for Beneficial Insects

More than one organic gardener has opened a box of ladybugs to employ as natural garden pest control, only to watch a bright red-orange cloud fly away into the neighbor's garden! Beneficial insects are the most environmentally-friendly way to prevent slugs, bugs, and caterpillars from destroying the garden, but first you have to get them to hang around.

An insectary garden is a type of companion gardening that invites insects to live within, providing the right kind of food and shelter they need to survive and procreate. Insects require different types of food at different stages of their lives. An insect garden provides supplemental food sources for times when the pest population is low, and since some adult beneficial insects need pollen and nectar to survive.

When their needs aren't met, beneficial insects will leave your organic garden in search of a more desirable home. The particular plants you grow to attract them don't matter as much as having an assortment of plants of different heights, and blossoms of various sizes blooming from early spring through late fall, to provide ideal living conditions for the most effective variety of beneficial insect species.

You'll need patience while your beneficial insect population increases and begins to effectively eradicate the pests. The initial population of adult insects will reproduce in your organic garden, resulting in larvae that are even more voracious than their parents.. For example, an adult ladybug will eat about 40 aphids a day, but each larvae she produces will eat up to 400 aphids a day. The garden pest situation may begin to look worse before it gets better. Rinse off early infestations off with a strong spray of water, or pick them off by hand. Avoid the temptation to use any chemical pesticides on your garden, which can kill generations of beneficial bugs as well as garden pests.

Supplementing the Natural Beneficial Insect Population
When your naturally-drawn insects aren't populous enough to keep the pests under control, you may need to supplement them by buying the varieties you need from a garden supply store or online supplier. Ladybugs, green lacewings and trichogramma wasps are generally considered the most versatile of the beneficial bugs. Other common beneficial bugs include praying mantises, aphid midges, mealybug destroyers, whitefly parasites, pirate bugs and beneficial nematodes. The species and quantity you need depend on the size of your organic garden, which pests are attracted to the particular crops you are growing, and which beneficial insects prey on them.

Tips for Creating an Insectary Garden
Plant tiny early spring flowers to attract your initial population of trichogramma and other tiny parasitic wasps. Alyssum, domestic carrots, dill, statice, parsley, lemon balm and fennel are good choices.

Lower your standards when it comes to weeds. Many weeds make tiny, early spring flowers, so you may as well take advantage of nature's free bounty. Leave a few of the less troublesome ones in and around your garden. Queen Anne's Lace, wild carrots, alfalfa, rue, clovers and wild carrots all produce tiny spring flowers that attract beneficial wasps.

Low-growing herbs such as thyme, mints and rosemary will provide shelter for ground-dwelling beneficial beetles (who will also appreciate good mulch).

Hedgerows and shrubbery are natural insect habitats, and planting your garden close to them may entice beneficial insects living within to help you reduce your garden pest population. Place your garden where the plantings won't block the sunlight on your garden during the late mornings and early afternoons during the growing season.

Ladybugs overwinter in cold climates, huddling in masses under eaves on the north side of houses, under rotting debris, in crevices in logs, and other sheltered places. Find them before they are drawn out by spring weather and carefully move the colony to your garden area, placing them in a sheltered spot.

Ladybugs are attracted to flowers that have an umbrella shape, such as Queen Anne's Lace and dill, which gives them a sheltered spot to cling to underneath the blossoms.

Praying mantis egg cases can be difficult to find, but if you learn to recognize them you may find them in tree branches. Carefully cut a long section of twig containing the case, and lay the twig in the crook of a nearby tree, or tie it to a branch. Egg cases may also be found attached to walls and fences, but these can't be moved without damaging them.

Not all beneficial insects prey on garden pests, but are still a vital presence in your organic garden. Butterflies and honeybees aid in pollination, increasing your garden yield. Plant some flowers that are particularly attractive to them, such as bee balm, butterfly bush, and anise-hyssop. Your predator insects will take care of any plant-eating caterpillars that the butterflies produce!

Read more about beneficial insect species

Resources:
http://www.grinningplanet.com/2005/04-26/beneficial-insect-natural-pest-control-article.htm
http://www.finegardening.com/how-to/articles/attracting-beneficial-insects.aspx