Ain't No Bugs On Me

Dear Farm,
What are the best ways to repel mosquitoes in our yard without using chemicals? Should I use a bug zapper?

West Nile Nervous in PA

Dear W.N. Nervous,

Great Question! Let's start with the bug zapper. The University of Delaware conducted a study (Entomological News [107(2): 77-82]) where bugs were collected from a bug zapper in a suburban neighborhood nightly for an entire summer. Their results showed that only .22% (less than a quarter of one percent!) of the bugs killed were actually biting insects like female mosquitoes and female biting gnats. Of the rest killed, 48% were harmless aquatic insects from nearby water sources, an important food source for fish. Another 13.5% of insects killed were beneficial and predator insects, the kind that naturally keep pest bugs at bay. The bottom line here is this: Bug Zappers are Bad News!!

So what effective measures can be taken? Let's start with a basic lesson in the life of a typical mosquito. Mosquitoes need standing water to reproduce. Some varieties can go from egg to adult in as little as four days, but most average 10-14 days. Here is a handy picture from wuvcd.org to show you their quick life cycle:

It is amazing how quickly a puddle in a bucket or old tire can become filled with mosquito larvae, so the first step in controlling the buggers is to...

Check your property for standing water. If you can eliminate the breeding grounds, you can help eliminate the pests. Remember to frequently change the water in any bird baths, and thoroughly scrub the sides of them for any eggs patiently waiting for the water level to get high enough. Check your house's gutters for any obstructions. If you have a water feature such as a pond, consider adding a fountain of some kind so the water constantly moving. If this is not possible, there is a bacteria called Bacillus Thuringiensis Israelensis, or BTI, that can be added to the water to kill the mosquito larvae. BTI is considered non-toxic to humans and wildlife, but it should never be added to water intended for human consumption. You can learn more about BTI's advantages and disadvantages here. You can purchase it through several places including Gardens Alive.

Encourage Natural Predators. Did you know that bats consume huge quantities of insects each night, and some varieties prefer the tasty treat of mosquitoes? Building or purchasing a bat house is a great way to control the bug population while helping to provide a home for an important member of our ecosystem. Bat Conservation International (BCI) has a great informational website including what to look for in a bat house and free plans to build your own. They also answer many common concerns about the safety of having bats on your property.


The Candle Trick. Citronella candles have been used for a long time, since 1882 in fact, to repel mosquitoes. They work best when there is little air movement-this helps to keep the smell around.

Plants for Protection! If essential oils help repel the little beasts, why not try the real plants? Citronella oil is present in several plants, including citrona geranium (also called the citronella plant), lemon balm, lemon tyme, and basil. Lemongrass is actually a cousin to Mana Grass, the main source for citronella essential oil, so go ahead try that one too. At the farm we currently offer lemon balm, lemon thyme, and basil for sale. We may have some lemongrass available later in the season. Maybe next year we'll try growing the citrona geranium as well to complete our bug-free section.

Bring Out The Spray. Preventative measures are effective, but they do take time. Add to that the fact that mosquitoes can fly in from other places not so easy to control (up to 20 miles away!), and I'm sure they'll still be some around to eat you at twilight. At the farm, we've tried a few of the natural bug sprays on the market. Burt's Bees makes a yummy smelling eucalyptus and lemongrass spray. It is an oil base, so it worked nice as a moisturizer at the same time, but unfortunately it didn't seem to last for any longer than an hour or so. We didn't mind, but if you've got active kids running around trying to catch lightening bugs, it's hard to pin them down every 15 minutes for re-application. This year we're trying out one by Gardens Alive called Sting-Free. It's not greasy, has a nice light geranium-like smell, and the package claims it repels mosquitoes, ticks, and black flies for 3 hours. So far it's working nicely- we'll have to let you know how well it worked during peak bug season. We've also heard great things about a bug lotion called Green Ban, and there are plenty of options to make your own bug repellent using a variety of essential oils like peppermint, lavendar, bergamot, cedrawood, lemongrass, pennyroyal, and eucalyptus. You can mix and match or follow some handy tips from this NaturoDoc article.


You Are What You Eat. The final step you can take is to make yourself less appealing from the inside-out. The verdict seems to be mixed on the true effectiveness of diet in preventing mosquito bites, but rumors have it that if you limit your intake of sugars (especially white sugar and high-fructose corn syrup) and alcoholic beverages, eat foods high in thiamin and eat plenty of garlic, they'll prefer your more toxic friends. Either way, staying away from sugar, staying sober, and eating healthy sounds like a fine idea, bugs or no bugs.

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