Plants that Repel Mosquitos

Most of us want products that won’t further harm the earth, and you can’t get much more natural than plants. But their use to repel mosquitoes may remind you why chemical products became so popular.  When stuff doesn’t work well, we develop better stuff.

So is the case with mosquito-repelling plants. They’re better than nothing—and were probably simply awesome 250 years ago—but a survey of several state extension offices supports what we’ve already found: If you really need to repel mosquitoes, you need more sophisticated tactics.

That said, some plants do repel . . . a bit. Citronella and lemongrass are strong choices, as are lemon eucalyptus, catnip, sage, rosemary, lavender, peppermint, and marigolds. It’s the scent that repels those flying bloodsuckers, and the smell comes from the plant oil, which is why mosquito repellents often contain the oils of these plants. If you crush the leaves, you can get to the oil and get a stronger effect, but, of course, you need to use commonsense and not destroy the entire plant. (One geranium (Pelargonium citrosum) is marketed to repel mosquitoes, but experts say the scientific backing for its ability is lacking. It is a pretty flower, though.)

Research surrounding the use of these plants to repel mosquitoes is based on the effectiveness of the oil, not the plant itself. So, a garden full of these types of plants would be pretty, but you’d need an awful lot of them to get any effect. If your deck is large enough, you could fill it with these plants—emphasize citronella and lemon eucalyptus—but they would likely be in containers and need a lot of watering.

Our advice is that, if you really want to deter mosquitoes without chemicals, reach for oils from citronella, lemongrass, peppermint, or eucalyptus.

The Centers for Disease Control and Prevention (CDC) recommend mosquito protection by using screens on doors and windows, air conditioning, and never allowing any standing water on your property. Dump anything that holds water at least once a week to stop mosquitoes from laying eggs.  And try to avoid the peak mosquito-feeding hours of dawn and dusk.

Finally, mosquitoes carry disease, so you do want to avoid bites. The CDC says to choose repellents registered with the Environmental Protection Agency (EPA) and recommends mosquito repellents containing one of these ingredients:

• -DEET
• -Picaridin (KBR 3023)
• -IR 3535
• -Oil of lemon eucalyptus
• -Para-menthane-diol
• -2-undecanone