Catnip vs DEET: No Contest

Simple Garden Solutions For Summer Stings

Our daily deer visits have been made a bit more exciting by daily coyote sitings, possibly not unrelated. In any case, we are now hosting a limping faun, still spotted and tiny but seemingly sturdy despite the bad leg, as well as its mama and assorted kin. We’ve all been holding our breath, hoping not to see any gory culture clashes, but so far, the deer have managed to evade the coyotes. It does seem a little ironic to be supplying fresh water to the very creatures that have been relentlessly ravaging my garden, but then, it’s hot, it’s dry, and what else is there for the poor critters to eat?

So that’s a bit of a sting, but the other kind are proving far more bothersome. Since the summer is so hot and dry, I’ve been surprised to find (or be found by) so many mosquitoes of an evening, until I finally figured out that they are finding breeding pools in the deep saucers that hold my large container plantings. Given that the saucers are keeping my crops from frying in the summer heat, I guess I’ll accept the mosquitoes as part of the bargain. However, I’m more accepting than I might be because I grew so much catnip this year.

A Better, Brighter Catnip

If that sounds like a non sequitur, read on. While most of my garden is on my extensive deck, I finally planted a real one this spring, despite the deer. To keep them from feeding too heavily, I planted a wide range of less-preferred perennials and shrubs, interlaced with lots of annuals that have never (in my experience so far) been deer fodder. Along with the usual zinnias and marigolds, I planted several dozen catnip plants. Rather than the usual drab, sad-looking plants, my catnips are strapping, colorful creatures called Cat’s Meow, a selected form from Holland that is larger, brighter, and far more floriferous than the straight species.

Indeed, my Meow plants stretch nearly 3 feet high and some are 5 feet across. They are growing in mounded sandy loam top dressed with fish compost, a combination that makes all the herbs in the new garden very contented. Indeed, pretty much everything I planted is proving to be much happier in sandy loam than they ever were in my heavy clay soil. Catnip (Nepeta cataria) is a homely cousin of ornamental catmint (Nepeta faassenii or N. mussinii), the classic English border edge plant. It’s generally grown as a cat-pleasing or medicinal tea herb, and rightly so, since its dusty grey-green foliage certainly makes our cats happy, but it also seems rather deer repellant, which is a very pleasant bonus.

And Bite-Reducing

Best of all, the foliage can be made into concoctions that repel mosquitoes as well as deer. Nearly a decade back, researchers at Iowa State University were looking for safer alternatives to DEET. Currently the most common active ingredient in commercial mosquito and bug repellents, DEET is also a dangerous chemical for humans, especially children. A study carried out at the Duke University Medical Center revealed that DEET can cause brain cell death and may trigger behavioral changes indicative of neurological damage in rats after frequent or prolonged use.

During their search, the ISU team investigated several plant essential oils commonly used as insect repellents by organic gardeners. The most promising substance turned out to be an essential oil found in catnip that is ten times more effective at repelling mosquitoes than DEET and its fellow toxic chemical repellants. A few years later, the ISU Research Foundation applied for a patent for the use of catnip essential oils and compounds. Today, you can buy a range of commercial bug-off products that are catnip oil based, but you can also make your very own. Here are a couple of recipes I’ve been using for the past few years. Both do a fine job of keeping mosquitoes and no-see-um’s at bay during our warm summer evenings.

Catnip Mosquito Spritz

2 cups catnip, stemmed
3-4 cups unflavored rice vinegar

Rinse herbs, roll lightly with a rolling pin, then place them in a clean quart jar and cover with vinegar. Seal jar and store in a dim cupboard for two weeks. Shake jar lightly every day or so for two weeks. Strain into a clean jar, seal and refrigerate unused for up to 6 months. To use, spritz on exposed skin and around outdoor dining area. Makes about 3 cups.

Catnip and Rosemary Mosquito Chasing Oil

2 cups catnip, stemmed
1 cup rosemary, cut in 6″ sprigs
2 cups grape seed oil or any light body care oil

Roll herbs lightly with a rolling pin and pack into a clean jar. Cover with oil, seal jar and place in a cool, dark cupboard for two weeks. Shake jar lightly every day or so for two weeks. Strain into a clean jar, seal and refrigerate unused for up to 8 months. To use, rub on exposed skin. Makes about 2 cups.