Beneficial Insects are no different than other wildlife in the garden.
To survive they need a relatively undisturbed place in the garden with adequate food sources, access to water, shelter from the elements and their predators and places to lay eggs.
While they eat other bugs, many predator insects also need pollen for protein and nectar for the carbohydrates provided by flowering plants.
A group of such plants is called an insectary.
Insectaries are usually groupings of preferred plants such as blooming annuals, perennials, shrubs and trees where the insects can live undisturbed and venture to other parts of the garden to feed and mate.
This is beneficial for you and the insects you want to attract.
Research has shown that the most effective way to create the proper environment is to plant preferred plants in either groupings around the garden or in hedgerows along a property line or a lightly used part of the yard.
These groupings or hedgerows then need to be maintained with the insects in mind.
Living with a few weeds may also help draw good insects because some of them are a highly favored source of pollen and nectar.
Plants in the insectary need to be of varying heights and densities to give insects a flexible habitat.
Some insects live near the top of plants while others like ground beetles live near the soil and need the protection of dense cover.
Other like lacewings lay their eggs in shady, protected areas in dense foliage.
The best flowers to plant for beneficial insects are those with small flowers in large clusters. Because many of the beneficial insects are small, a small flower is easy to get into to get pollen and nectar.
The small insects may drown trying to get into large flowers.
Flower clusters that are flat or composed of single petals also make good landing places and places to search out a mate.
You should have something blooming in the insectary from early spring to late in the fall.
Because these insects are out as long as the detrimental insects are active, they need access to food sources throughout the season.
Again, research has also shown that providing a variety of flowering plants not only sustains the adult insects but also allows longer survival periods and higher breeding rates.
While there are dozens of plants that these insects like, three families of plants in particular are very popular with the beneficial insects.
In any case, it is important not to plant noxious weeds or other invasive species.
Be sure to check your state’s or province's noxious weed lists first.
The Apiaceae or carrot family (formerly the Umbelliferae) is comprised of more than 3,000 species of plants many of which are very familiar to us.
The family includes common food favorites such as carrots, parsley, coriander, dill, fennel (invasive in western Washington), parsnips, cumin and garden plants such as sea holly, lovage, angelica and wild carrot.
The Apiaceae is characterized by flat topped flowers held up on hollow stems.
The flowers are a mass of smaller individual florets that the beneficial insects find very easy to get nectar and pollen from and are an easy place to land.
The Brassicaceae or mustard family (also known as the Cruciferae) is another large group of plants beneficial insects find attractive because of their small but abundant flowers.
Culinary members of the family include broccoli, Brussels sprouts, cauliflower, cabbage, turnip, rapeseed (canola), horseradish, Chinese cabbage and others.
Herbaceous members of the family include bittercress, alyssums, tumble mustards and arabis.
Vegetable gardeners wanting to encourage beneficial insects should let a few broccoli plants flower to attract them.
The third family is the Asteraceae which includes asters, sunflowers and daisies.
Gardeners prize members of this family for their color and bloom periods that starts in mid summer and goes well into the fall; perfect for keeping insects around late in the season.
The flowers are a composite flower made up of rays of ray-shaped petals around a center of tiny disk flowers.
If all your plantings work, you should be able to attract native populations of predatory insects to your garden.
Sometimes however, there aren’t enough around or you need a large quantity to go after a particular pest.
Beneficial insects can be purchased from garden centers or online from several sources.
Local garden centers are likely to have the most popular varieties while the online sources will have a broader selection.
Remember the insects are alive and will need to be deposited in the garden immediately after delivery or purchase.
Read the instructions carefully so that you put them in the right place in the garden.
The bugs will disperse around the garden on their own and a few will venture away from it. There is no way to keep them in one place especially if there isn't enough food or if they are wanderers by nature. Lady bugs are notorious for this but they will set up shop somewhere close and be back when conditions are right.
Predator insects are a great ally in the garden especially when they are on the job 24/7. Adapting our gardens and our perspective is a small change to make to encourage them to establish themselves.
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