This time of year, the skies are full of migratory birds and butterflies that are returning and need places to rest and nest. The National Wildlife Federation has designated May Garden for Wildlife Month, and whether you have an apartment balcony, a suburban backyard, or honest-to-God acreage, you can qualify for the organization’s Certified Wildlife Habitat program—all while growing food for your table.
We’re squeaking in under the wire here (it’s May 28, after all), but no matter. Providing food, cover, and water for wildlife is relatively simple, and the resulting low-maintenance landscape is a boon to gardeners with demanding day jobs—or seasonal laziness disorder.
A Few General Tips
• Eliminate the use of insecticides. Insects are the main food source for many bird species; they’re an important source of protein and fats for juveniles in particular.
• Reduce the size of your lawn. Turn your version of the back 40 into a wildflower meadow, for instance, or plant milkweeds, goldenrod, or a plot of sunflowers. Vines such as grape and American bittersweet (avoid Chinese bittersweet, which has become a rampant weed in the Northeast) are popular with many bird species.
• Get rid of invasive plants that outcompete native species. Your local USDA Cooperative Extension System office will have a wealth of information about which plants to pull out.
• Think year-round. Select a variety of native plants to offer year-round food in the form of nectar, seeds, and berries. The Lady Bird Johnson Wildflower Center has lists of recommended native plants by region and state.
Trees are basically lifeboats for birds, especially in an unfriendly urban sea. Native Landscapes, an environmentally diversified landscape design firm in the Hudson Valley, has a helpful list of native trees (and shrubs) that attract birds, and you’ll discover that there are varieties to suit gardens of every size. If you have the room, plant fruiting trees that ripen at varying times for a long-lasting food source. Hollies are one good option: Their berries ripen in the fall and persist throughout the winter, birds feel safe in the thick growth, and the prickly leaves discourage most predators. (Buying tip: Some species, such as the American holly, aka Christmas holly, have separate male and female plants, and for the female to bear fruit, a male pollinator is needed. The Missouri Botanical Garden has more details.)
Another tree that needs a male pollinator is the eastern red cedar, but the cone-producing female is what Edie Parnum, at Backyards for Nature, based in southeastern Pennsylvania, calls a powerhouse. “Warbler, Eastern Bluebird, and Northern Mockingbird are among the 54 species of birds that eat its long-persisting berrylike cones during the cold months. Cedar Waxwings are so named because they’re fond of cedar cones,” she writes, also noting that “Song Sparrows and other birds use the dense foliage for nesting places and shelter.” Don’t be tempted to buy the similar-looking Leyland cypress, she cautions; it’s a nonnative that offers little for wildlife. A row of (evergreen) cedars, which tolerate a variety of soils and dry to moist growing conditions, will not only provide shelter for birds but offer humans privacy and even energy savings. “If planted on the north side of your house,” Parnum adds, “they will create a windscreen.” In other words, what’s not to love?
Even dead trees are useful: Their nooks, crannies, and hollows provide nesting opportunities, shelter from harsh weather, and an insect smorgasbord for birds. As for leaf litter in the yard, leave it be. Those decaying leaves are paradise for the centipedes, crickets, and earthworms that birds love; some species of butterflies overwinter as eggs and chrysalides in them too. If you have a brush pile in the corner of the yard, that’s great; some bird species will hunt, roost, or nest in it.
For space reasons, it’s necessary for me to cherry-pick (sorry) examples, but I’d be remiss if I didn’t mention native oaks, such as the northern red oak, the Kellogg oak, and the coast live oak. They can grow to lofty heights and need space to spread their branches but can support more than 550 species of protein-rich caterpillars—the food that birds most commonly feed their young. The National Wildlife Federation, the U.S. Forest Service, and Doug Tallamy, University of Delaware entomologist and author of Bringing Nature Home: How You Can Sustain Wildlife With Native Plants, are working on a set of state-by-state lists of caterpillar-friendly plants; it should be published this fall, so stay tuned. Oaks are also classic shade trees, important to note at a time when climate change is on everyone’s mind. Cool, shaded areas provide critical refuge to wildlife riding out dry or hot conditions.
If you don’t have room for more than one mature tree, supplement it with an assortment of shrubs or a thicket of bramble fruit, such as blackberries, raspberries, or boysenberries; their prickly canes offer great cover and nesting sites. Providing a year-round water source, in a birdbath or other container, is also key. Put it a good 10 feet from shrubs or other cover that may harbor the neighbor’s cat or other predators.
Butterflies are drawn to sunny spots that are protected from the wind. Leaving a wild, weedy border or patch in your garden may look like benign neglect, but it’s also a savvy strategy for increasing butterfly populations; Queen Anne’s lace, milkweeds (more about them in a sec), nettles, burdock, and thistles are all ideal butterfly-friendly weeds.
Perennials and long-blooming annuals produce a progression of blooms, ensuring a supply of nectar that lasts for months. Native Landscapes, mentioned above, also lists native wildflowers, shrubs, and trees that attract butterflies and hummingbirds.
On one hand, flowers that attract butterflies couldn’t be simpler to incorporate into any garden: They include old-fashioned favorites such as sweet william, daisies, marigolds, zinnias, single-flowered hollyhocks, and sunflowers. But sources such as Attracting Birds & Butterflies: How to Plan and Plant a Backyard Habitat, by Barbara Ellis, explain that a successful butterfly garden includes plants for butterfly larvae (caterpillars) to eat as well as nectar for adults, and that’s where things get a bit more complicated. For example, the nectar of the so-called butterfly bush (Buddleia) will attract adult butterflies, but the plant itself can’t be eaten by larvae. Although some species (such as American painted lady, viceroys, and western tiger swallowtails) lay eggs on a variety of plants, other species require a specific type of plant for their larvae.
Milkweeds, for instance, are the required host plants for caterpillars of the monarch butterfly, and that has gotten the once-common orange-and-black beauty into a whole heap of trouble. Monarch migration from the U.S. and Canada to Mexico has been considered an endangered phenomenon for about 20 years, but adverse weather conditions, farmland expansion (more than 25 million new acres in the U.S. since 2007), and the rapid increase in fields planted in G.M. soybean and corn that tolerate glyphosate herbicides such as Roundup have placed monarchs in even greater danger. “The American Midwest’s corn belt is a critical feeding ground for monarchs, which once found a ready source of milkweed growing between the rows of millions of acres of soybean and corn,” wrote Michael Wines in the New York Times in March 2013. “But the ubiquitous use of herbicide-tolerant crops has enabled farmers to wipe out the milkweed, and with it much of the butterflies’ food supply.”
Arizona-based conservation scientist Gary Nabhan is among those who are cultivating sanctuaries of healthy farmland and gardens scattered “like island refuges across the continent,” he writes in a piece in the spring 2014 issue of Heirloom Gardener. One of these “islands of hope” is managed by native seed saver John Anderson of Hedgerow Farms, near Winters, Calif. The Xerces Society for Invertebrate Conservation joined forces with Anderson, using his methods for restoring native milkweed habitat. As part of Project Milkweed, the Xerces Society has created a national directory of milkweed seed vendors to help the public find sources of seed. The Monarch Joint Venture’s Milkweed Market offers flats of milkweed plugs (plants) grown from seeds sent to Monarch Watch by volunteers from across the country.
Once you’ve made your garden a biodiverse oasis for birds and butterflies, you’ll want to know what all those beautiful creatures are. Audubon’s Field Guide to North American Birds and Butterflies app is a great value at $4.99. The free Merlin Bird ID app, from the Cornell Lab of Ornithology, is terrific as well; it draws on more than 70 million observations from the eBird citizen-science project.
Lastly, a note for those who are allergic to bees or frightened of them on principle: Don’t panic if they crash your garden party. They aren’t flying around looking for people to sting; they’re far too busy collecting pollen and nectar to feed their young and themselves. The Garden Task Force of the North American Pollinator Protection Campaign puts the risk into perspective and gives tips on how to avoid getting stung.