How To Repel Mosquitoes From Your Yard All Summer

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Controlling mosquitos is a big job, but a widely available, inexpensive product called a mosquito dunk can make it a lot easier. A mosquito dunk is flat, donut-shaped, and looks like a cookie, and it doesn't actually repel mosquitoes — in fact, it sort of attracts them. The dunk sits in stagnant water, where mosquitoes gather to lay their eggs. To kill the larvae that hatch there, it releases the toxic bacterium Bacillus thuringiensis israelensis (Bti). Fewer surviving larvae means fewer adult mosquitoes to bother you, so, in the long run, a dunk is as good as any repellent.

Bti is a benign organism, harmless to anything but the larvae of mosquitos, black flies, and some other dipteran species, so you don't have to worry about harming bees, butterflies, fish or other beneficial wildlife you want in your garden. However, it won't harm adult mosquitoes either, which means you'll have to wait for them to die off before you notice any difference in the bug population. In other words, dunks aren't an instant solution to an existing mosquito problem — but they are useful if you think ahead and set traps early in the season. 

One of the first steps in mosquito control is to eliminate any pools of stagnant or standing water in your yard, as these can become breeding grounds for these bugs. If you look around, you might be surprised at how much standing water you find: It can collect inside toys that have been left around, in open jars, on tarps, and in old buckets. Even the water that pools at the base of potted plants attracts mosquitoes.  

You may need to utilize drainage solutions to get rid of standing water, but you'll also want to leave some in places that you can bait with mosquito dunks. A birdbath or fish pond is a perfect place for a dunk, since Bti won't harm birds or fish. Otherwise, you can fill 5-gallon buckets with water, leaves, and sticks to create "buckets of doom" for the flying pests. Drop a dunk into each one and cover them with a wide mesh screen to keep pets out. 

You don't have to use an entire dunk for it to be effective; if you break it into pieces, you'll have more to go around, and you'll be able to set out more traps. And the more you set, the more mosquitoes you'll prevent from growing into adulthood. Dunks remain effective for about 30 days, so try to make replacing them part of your monthly routine — this will be a great step toward a mosquito-free summer.