Sunday, August 02, 2009

Luring Bats Into Your Garden

It is easy to encourage the creation of gardens which attract butterflies, hummingbirds, or songbirds. But bats? Rather than appreciate these fascinating night fliers, most people tend to react with a loathing inspired by superstition and misunderstanding. However, inviting bats into your yard and garden is one of the easiest and safest methods for eliminating thousands of pesky insects a night, including the much dreaded mosquito.

In fact, bats are the primary predator of night-flying insects across the globe. There are approximately 1,000 species of bat worldwide, which make up almost one-quarter of all mammal species on Earth, with 10 species found in my old stomping grounds of Maryland alone. The most common bat in the Mid-Atlantic area is the little brown bat (Myotis lucifugus), followed closely by the big brown bat (Eptesicus fuscus).

For the most part, our local little brown bat is known to consume hundreds of insects an hour, up to one-third its body-weight every half-hour, from swarms of mosquitoes to gnats, gypsy moths, and a host of beetles. Visitors to marshes and wetlands just after dusk are often greeted by the aerial antics of numerous bats swooping low over the water to gulp down thousands of mosquitos and midges.

Regrettably, rather than recognize these peaceful creatures as partners to residents and farmers in maintaining troublesome insect populations, people continue to perpetuate absurd myths about bats becoming entangled in women’s hair, carrying rabies, and biting children with vampiric zeal. In actuality, bats are among the most gentle mammals on earth. They are not rodents or related to mice at all. And while all mammals can “get” rabies, bats have a much lower incidence rate than raccoons or skunks, and one statistic indicates that there have only been ten confirmed cases of humans contracting rabies from bats in 30 years. Lastly, bats are not blind at all. All bats can see, although they rely on echolocation and smell, more than sight, to identify and capture prey.

Developing a bat garden is actually quite easy, certainly easier than buying a batmobile or fighting criminal masterminds. The goal is to landscape with plants which attract night-time pollinators -- nice juicy bat-treats like many of the moth species -- which will in turn tempt bats to visit and hang out in your yard, perhaps ultimately taking up residence in the area.

Most of the plants needed are commonly found at garden centers and are as much a delight for the human senses as for the fluttering moths. Herb gardens alone attract many nighttime pollinators. Why not put in a small kitchen herb garden using both common and garlic chives, marjoram, oregano, lemon balm, borage (which also attracts swarms of beneficial bees during the day), sage, and some of the fragrant mints, from English pennyroyal to apple and chocolate mint, among others?

Elsewhere in your garden you should consider a number of plants similarly renowned for their evening scent. Welcome your bat comrades while you sweetly perfume the warm summer evening around your home. Desirable choices include jasmine, gardenia, and the outlandish night-blooming cereus, all of which are best grown in containers and taken indoors in winter. In addition, consider standard garden fare such as evening primrose, nicotiana, sweet rocket, night-scented or evening stock, bouncing bet, cream-colored petunias, Franciscan nightshade, dame’s rocket, gas plant, soapwort, and night-blooming gladiolus.

One of the most exquisite and versatile selections, which combines fragrance with large, showy blooms, is moonflower (Ipomoea alba). Related to morning glories and sweet potato vine, moonflower is a fast-growing vine which can reach up to 20 feet, with large six-inch wide blooms which open at night. Moonflower can be trained to a trellis, or simply allowed to sprawl over a rock wall or pile of stones.

Most of the species cited above offer bright white or cream-colored blooms which can readily brighten your garden beds at night, and even add a sensuous, romantic air when visited under moonlight. Of course, you can also plant flowers in a range of colors which will add sparkle to your daytime garden, while still attracting nighttime pollinators. Among the most favored are salvias, phlox, bachelor’s buttons, four o’clocks, silene, and heliotrope.

Beyond simply attracting moths and other flying insects to get a hungry bat’s attention, you can provide some additional habitat elements, and potentially, even a roosting site that will guarantee bat loyalty for years to come.

Building a bat cave might be out of the question, but what about a bat pool? If you have thought about a small pond or water feature for your garden, this might be just the impetus you need. The bat pool can be anything from a plastic tub or whiskey barrel buried in the ground, to an actual pond liner or old bathtub. Make sure that you line the perimeter of the “pool” with flat stones which will allow bat visitors to make their way to the edge of the water and drink. Be sure to either aerate the pond or basin, or at least add a few fish to eliminate potential mosquito larvae.

You might also wish to help create a roost for bats. For example, solitary bats might be interested in nesting in a rock retaining wall constructed with large 10-12 inch wide stones, which include a number of good-sized nooks. Smaller spaces in the wall can be filled with a bit of soil and planted with thyme or other creeping groundcovers.

For the most part, bats tend to live in hollow trees, caves, abandoned buildings, behind loose boards or shingles, and, though not a preferred address, in accessible attics. The attic or belfry option is generally not encouraged.

On the other hand, there are a number of bat houses sold through garden centers, catalogs, and nature-related gift shops. Unfortunately, it is generally believed that most of these bat houses, however well-intentioned, will go untenanted indefinitely. Some naturalists have suggested placing bat guano under a new box to provide, perhaps, a lived-in look, and thereby attract new lodgers. That might be asking a lot of the average gardener.

The best bet might simply be to allow bats to find their own roosts, while ensuring that they will stay in your area by providing some habitat features and a welcome meal ticket. You will find, in time, a special sense of wonder as you watch visiting bats cavort through the night sky overhead, usually starting at or just before nine o’clock, and in between sightings, you can drink in the rich scent and subtle beauty of your new evening garden.

For more information on bats and bat conservation, visit or contact Bat Conservation International, P.O. Box 16203, Austin, TX 78716;

Copyright 2009, Joseph M. Keyser

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