Creatures of the Night: Landscaping for PA's Native Bats

Halloween is here! , The streets will soon be filled with eager trick-or-treaters, porches will be glowing with jack-o'-lanterns, and many houses will have a swarm of plastic, red-eyed bats hanging from the eaves on fishing line. We love to use bats as ome of the unofficial spooky mascots of Halloween. We associate them with haunted houses, vampires, and the eerie, unseen darkness of the night.

But when the plastic decorations come down on November 1st, how much thought do we give to the real creatures of the night?

In reality, Pennsylvania’s native bats are not monsters; they are the unsung, apex predators of the night sky. And right now, they are starring in a real-life horror story. Decimated by a devastating fungal disease called White-Nose Syndrome and pushed to the brink by the relentless expansion of sterile, manicured suburban lawns, our local bat populations are in freefall.

If we want to continue enjoying summer evenings on our patios without being swarmed by mosquitoes, we need to rethink how our landscapes function after the sun goes down. This Halloween, it is time to move beyond the plastic decorations and start inviting real bats to your landscape. By challenging the norms of traditional landscaping, you can transform your property into a sanctuary for Eastern Pennsylvania’s most misunderstood and ecologically vital mammals.

A Billion Dollar Night Shift

To understand why we need to landscape for bats, we first need to understand the sheer volume of ecological work they perform while we sleep.

Pennsylvania is home to several native bat species, most notably the Little Brown Bat and the Big Brown Bat. These small mammals are insectivores, meaning their entire diet consists of flying insects. And their appetites are staggering. A single nursing female Little Brown Bat can consume her entire body weight in insects in a single night. This equates to thousands of mosquito-sized insects per bat, every evening, from spring through fall.

This nocturnal feast provides an invisible, massive economic and environmental benefit. Bats serve as the primary natural control for agricultural pests, saving the U.S. agricultural industry billions of dollars a year in crop damage and pesticide costs. In our own backyards, they are the best, chemical-free mosquito control.

Yet, the traditional American landscaping ethos actively starves them. We mow our lawns down to two inches, spray broad-spectrum insecticides to kill the "creepy crawlies," and plant imported ornamental shrubs that provide little to zero ecological value. We have built suburban environments that are practically devoid of the native insects that bats rely on to survive.

Feed the Food: The Science of the "Moon Garden"

If you want to attract bats to your property, you cannot simply put out a bowl of food like you would for a stray cat (or trick or treatirs). You have to feed their food.

While bats do eat mosquitoes, their absolute favorite, high-calorie meals are night-flying moths and beetles. To get bats, you need moths. To get many moths, you can plant a very specific type of landscape: a Moon Garden.

A Moon Garden is a landscape designed specifically to come alive after dusk. Many of our popular garden flowers, like Coneflowers and Black-Eyed Susans, are day-bloomers. Their bright colors attract diurnal (daytime) pollinators like bees and butterflies. But night-flying moths navigate by moonlight and scent. Therefore, a Moon Garden focuses on native plants that feature pale, white, or silvery flowers that reflect the moonlight, and that release heavy, sweet fragrances exclusively in the evening.

By planting a Moon Garden, you are essentially setting up a buffet for native moths, which in turn sets up a buffet for native bats. Here are a few native plants to anchor your nocturnal landscape:

1. Common Evening Primrose (Oenothera biennis)

This is the absolute powerhouse of the Pennsylvania Moon Garden. As the name suggests, the bright yellow, cup-shaped flowers of the Evening Primrose stay tightly closed during the heat of the day. But as the sun sets, they rapidly unfold; you can actually stand in your garden and watch them pop open. They release a sweet, lemon-like scent that is irresistible to large, night-flying Sphinx moths (the equivalent of a filet mignon for a hungry bat).

2. White Wood Aster (Eurybia divaricata)

For the shaded edges of your property, White Wood Aster is a phenomenal late-season bloomer. In September and October, it produces masses of tiny, star-like white flowers. Under the moonlight, a large drift of White Wood Aster practically glows in the dark, acting as a highly visible landing pad for nocturnal pollinators.

3. Native Phlox (Phlox paniculata or Phlox maculata)

While many cultivars exist, seeking out straight-species native tall phlox adds incredible value to the night garden. The pale pink and white varieties possess a strong, sweet fragrance that peaks in the humid evening air, drawing in a wide variety of nocturnal moths and beetles.

Danger of the Spotlight

You can plant the most beautiful, moth-rich Moon Garden in the neighborhood, but if you do not address your outdoor lighting, you will inadvertently create a death trap for the bats you are trying to help.

As we discussed in previous posts, Artificial Light At Night (ALAN) is biologically destructive. Moths exhibit positive phototaxis; they are irresistibly drawn to artificial light. If you leave a bright LED floodlight on all night, you will suck all the moths out of your Moon Garden and trap them in an exhausting, endless orbit around the bulb.

You might assume that concentrating all the moths around a single streetlight would make hunting easier for a bat. But bats rely on the deep dark to survive. They use echolocation to hunt in pitch blackness, where they are invisible to their own predators. If a bat is forced to fly into the harsh glare of a suburban floodlight to catch a moth, it is instantly exposed. Owls, hawks, and neighborhood cats quickly learn to camp out near artificial lights, easily picking off the bats as they swoop in.

To make your yard safe for bats, practice Dark Sky lighting. Put your security lights on motion sensors, so the yard remains pitch black when not in use. Ensure all path lighting points straight down, and swap out your harsh, blue-white LED bulbs for warm, amber-toned lights (under 2700 Kelvin), which are virtually invisible to night-flying insects.

Master the Bat Box

Food and darkness are critical, but as the temperatures drop, shelter becomes the deciding factor for survival.

In a natural, untouched forest, bats roost in the peeling bark of dying trees (snags) and in deep, hollowed-out tree cavities. In suburbia, we aggressively cut down every dead tree the moment it leans, effectively bulldozing the bats' natural housing market. If you don't have a safe, standing dead tree on your property, the best alternative is to install a bat box.

However, the accepted norm for bat boxes is often dead wrong. People buy cheap, tiny, single-chamber boxes from hardware stores, nail them to the trunk of a living shade tree, and wonder why no bats ever move in.

Bats are incredibly picky about their real estate, primarily because they need very specific thermal conditions to safely raise their pups in the summer, and to stay warm during the chilly transitional weeks of spring and fall. If you want to successfully host a colony, you must follow the science of bat box installation:

1. Go Big and Multi-Chambered

Skip the tiny, birdhouse-sized boxes. Successful bat boxes are large and feature multiple vertical chambers (crevices) inside. This allows the bats to move around within the box to find the exact temperature they need as the sun moves across the sky.

2. The 15-Foot Rule

Never nail a bat box to a tree. Trees provide too much shade, and the branches provide easy access for climbing predators like snakes, raccoons, and cats to reach in and grab the bats. Instead, bat boxes must be mounted on a freestanding wooden post or directly on the side of a building, at least 15 to 20 feet off the ground. This height gives the bats the necessary "drop space" to initiate flight when they exit the box.

3. Chasing the Sun

Temperature is everything. In the Mid-Atlantic climate of Pennsylvania, a bat box needs to receive a minimum of six to eight hours of direct sunlight every day to stay warm enough for the colony. The box should face South or Southeast to catch the morning sun and warm up quickly after a cold night.

Move Beyond the Decorations

This Halloween, as you hand out candy beneath the plastic bats swaying on your porch, take a moment to look out at your landscape. We have spent decades trying to sanitize the night, erasing the dark with floodlights and replacing complex native ecosystems with flat, chemical-laden lawns.

But true landscaping is about stewardship, not just aesthetics. By planting a fragrant, glowing Moon Garden, embracing the dark skies, and offering safe, elevated shelter, we can actively invite the magic of the wild back into our neighborhoods. You have the power to turn your property into a sanctuary for our native bats, the real creatures of the night. In return, they will spend the rest of their lives quietly, efficiently, and beautifully protecting it.