YOUR GARDEN — Plant Information

Pests, Problems, and Diseases

Mosquitoes and Gardening

Gardens and gardening are among the great joys in life. Mosquitoes can take a bite out of this pleasurable pastime unless preventive strategies are taken to minimize problems.

Description
West Nile virus is a disease that targets primarily birds, horses, and humans. It is transmitted through the bite of a mosquito that has previously bitten a diseased bird. Most mosquitoes in the Chicago area are annoying, but pose no serious health hazard. The Illinois Department of Health reports that fewer than one in 500 mosquitoes is infected with the West Nile virus, and the chance of a diseased mosquito biting you is very slight.

Chicago Botanic Garden Recommendations
To protect your garden from mosquitoes, you can take the following preventive steps. These guidelines suggested by the Chicago Botanic Garden are consistent with those put forth by the Illinois Department of Health and the Centers for Disease Control and Prevention, whose Web sites can provide additional information.

ELIMINATE AREAS OF STANDING WATER

The Garden recommends that efforts be focused on preventing the adult mosquito from breeding. In warm weather, an egg can develop into a larva and then into an adult mosquito in water that has been left standing for seven to 10 days. Prevent that cycle with the following precautions:

Once a week, from April to the first hard frost, check your property, garden, alley, home exterior and garage for any standing water or debris that might hold even the slightest amount of water. Household items might include cans, rain barrels, tires, buckets, garden tools, wheelbarrows, plant pot saucers and children’s toys.

Seal any hollowed areas of tree stumps.
Repair outdoor leaky faucets to prevent small pools of water from forming.
Empty pet water bowls daily.
Repair torn screens or loose windows.
Clean gutters of all debris so rain water never pools.
Check flat roofs for low spots that retain water.
Empty wading pools once a week. Store indoors when not in use.
Cover all larger pools if you are away for more than a week. Make sure pool covers do not accumulate water.
Change water in birdbaths at least once a week.
Install small pumps in ponds, aquatic gardens or fountains to aerate water, or add larvae-eating fish such as minnows. Commercially available “doughnut” or “mosquito dunk” products are composed of bacteria (Bacillus thuringiensis var. israelensis) that feed on mosquito larvae. This product is not toxic to other insects, birds or fish.
Empty outdoor fountains if you will be away for more than a week.
Check sewer drains, septic tanks and downspouts for any pooling water.
Cover rain barrels with tight-fitting lids or 16-mesh screening.

WEAR PROTECTIVE CLOTHING AND REPELLENTS

Wear socks and shoes, long pants, and long-sleeved, light-colored shirts when outside. Protect babies with mosquito netting.

Consult your family doctor for recommendations of mosquito repellents appropriate for you and your family. Research indicates that adult repellents containing 30 percent DEET offer protection for the longest time. Consult a pediatrician for children’s products. As with all insecticides, read and follow label directions.

PLAN YOUR GARDENING

Plan your gardening to avoid the times when mosquitoes are most likely to bite, the hours immediately before and after dusk or dawn. If virus-infected mosquitoes have been reported in your area, consider staying indoors during their peak biting periods. Mosquitoes favor shady, moist areas of a yard and rest in dense shrubbery; they are active from spring to the first hard frost in the fall.

For Additional Information
The website of your local mosquito abatement district can provide information about mosquito treatment in your area. For general information about mosquitoes and West Nile virus, visit these recommended websites:

Illinois Department of Public Health
http://www.idph.state.il.us/envhealth/wnv.htm

University of Illinois Extension
http://www.urbanext.uiuc.edu/westnile/about.html

Centers for Disease Control and Prevention
http://www.cdc.gov/ncidod/dvbid/westnile

For more information about gardening with mosquitoes, call the Plant Information hotline at (847) 835-0972.