With the arrival of warm, wet weather, mosquitoes are becoming more prevalent. Unfortunately, this can turn relaxing evenings outdoors into a constant battle against these buzzing and biting insects. Fortunately, there are several steps we can take to prevent mosquito bites while enjoying the outdoors.
Understanding mosquito biology
Before trying to manage mosquitoes, it helps to understand their biology. Mosquitoes have a complete life cycle, with four stages: egg, larva, pupa, and adult. The eggs are laid in or near water and hatch into larvae within a few days. The larvae feed on algae, bacteria, and organic debris in the water. They will pupate in the water, and eventually the adults will emerge. During warm weather, it can take as little as 7 to 10 days for a mosquito to complete this cycle, which can lead populations rapidly increasing.
Both male and female mosquitoes will feed on nectar and fruit juices. Additionally, female mosquitoes bite people and animals to get a blood meal. Female mosquitoes need a blood meal to produce eggs.
Start with the source: Eliminate standing water
Mosquitoes need water to reproduce, and they don’t necessarily need a lot of it; some need as little as one tablespoon of water to develop (about the size of a bottle cap). Therefore, removing, eliminating, or draining as many water sources as possible, such as clogged gutters, old tires, toys, and drip trays under pots, will help to reduce mosquito populations. Water in birdbaths should be emptied and replaced weekly.
If standing water can’t be removed, for example, in an ornamental/garden pond, water can be treated with Bacillus thuringiensis israeliensis (Bti). Bti is a naturally occurring bacterium that kills mosquitoes but does not harm humans, pets, fish, or other wildlife.
Make your yard less appealing
Most mosquitoes are most active around dawn and dusk. During the day they seek out cool, shaded, and humid areas where they can rest. Avoiding dense plantings, pruning plants to increase air flow, and keeping grass mowed can make the area around a home less attractive to adult mosquitoes.
Avoid mosquitoes
Because most mosquitoes are most active at dawn and dusk, limiting outdoor activity during those times (often easier said than done) can reduce the chances of being bitten. Mosquitoes are weak fliers, so if you are outdoors in the evening, using a fan can help keep them off people.
Choose the right clothing
Mosquitoes tend to be attracted to darker colored objects. Wearing light colored clothing can make you less attractive to mosquitoes. Additionally, loose-fitting long-sleeved shirts and long pants made of tightly woven materials can help prevent mosquitoes from biting you through your clothing.
Use repellents
Insect repellents are among the best and simplest ways to prevent mosquito bites. There are a variety of different EPA-registered insect repellents:
- DEET
- Picaridin
- IR3535
- Para-menthane-diol (PMD)
- Oil of lemon eucalyptus (OLE)
- 2-undecanone
Clothing can also be purchased treated with permethrin, or you can treat it yourself. Permethrin is an insecticide that kills or repels mosquitoes and can provide protection after multiple washings.
Whether using repellents or treating clothing with permethrin, make sure to read and follow all label directions and reapply as directed.
Good Growing tip of the week: When applying insect repellent, make sure to apply it after sunscreen. If sunscreen is applied over repellents, they will not be effective.
By Ken Johnson, Horticulture Educator, University of Illinois Extension
