Royal Hybrid Sunflower planting, abuzz with insect life. Photo credit: Hillary Alger, Johnny's Flower and Farm Seed Product Manager.
Beneficial insects need food and shelter if they are to control pests of vegetable, flower, or herb crops. An insectary planting of flowering plants will greatly increase the likelihood that predators and parasitoids will hang around and help with pest management. An insectary planting can be reserved entirely for beneficials, or it can be small, unharvested areas of valuable crops such as flowers and herbs.
Here are some types of plantings that can serve as insectaries in your farmscape.
Many plants grown to improve soil fertility and tilth are also attractive to beneficial insects when they are allowed to flower. Buckwheat is one of the best, especially because it flowers over a prolonged time period. Other cover crops that provide food and shelter for beneficials include the clovers, hairy vetch, cowpeas, and alfalfa. Growing cover crops in numerous small sections throughout a field keeps the beneficials close to the cash crops.
Often grown in strips among cash crops, grasses and grains provide refuge for ground beetles and spiders, and a shady place to lay eggs for other beneficial species.
Several families of flowers are particularly attractive to beneficials. Plants in the Apiaceae family (known as Umbelliferae in some circles) produce umbels of tiny, aromatic flowers that are a good source of nectar. The family includes Angelica, Ammi, anise, carraway, carrot, cilantro, dill, fennel, parsley, Queen Anne's lace, tansy, asafœtida, and yarrow. The mint family, Lamiaceae, produces tiny flowers with a lower "lip," a perfect tubule that provides access to beneficial insects (and hummingbirds). It includes bee balm, basil, catnip, lavender, lemon balm, marjoram and oregano, peppermint, sage, and many other strongly aromatic, useful, and beautiful herbs. The Asteraceae is another large family that provides abundant and easily accessible pollen. Many cut flowers are members of this family, including asters, sunflowers, blanket flower, coneflower, cosmos, and goldenrod.
Trees and shrubs
Permanent hedgerows provide refuge for many types of beneficials, and will be especially attractive if they include black locust, elderberry, Euonymus (burning bush), golden bells (Forsythia), willows, and Prunus species.
This is only a generalized list of plant materials that can serve as insectaries. A large proportion of flowering plants, including both agricultural crops and those in natural communities, are pollinated by insects, and the majority of insects are either beneficial or neutral.
If you look for plants in your area abuzz with insect life, those will make good candidates for farmscaping your fields and gardens. In regard to habitat conservation and avoiding invasive plant issues, remember that native plants attract and support native insects.
The presence of insectaries on your land, or within your protective structures if you practice controlled environment agriculture, can enhance quality and yield, diminish the need for inputs, and support resource conservation. Johnny's offers a line of seed varieties known to Attract Beneficial Insects, including a Bee Feed Mix and our Beneficial Insect Attractant Mix, as well as technical advice needed to successfully manage pollinator populations. To learn more, see Attracting & Putting Beneficial Insects to Work and our list of further reading.