Gardening for the Birds
Continued expansion of housing developments is reducing and degrading habitats for native species, but your garden can provide valuable wildlife habitat, especially for birds. In the spring, North Carolina is home to several groups of native birds. Neotropical migrant birds, which include tanagers, orioles, and buntings, are returning from their winter feeding grounds in Central and South America. Some will breed and nest here, while other species are just stopping by before heading further north. Resident bird species, like chickadees, cardinals, robins, and bluebirds, do not migrate and stay here year-round. Providing appropriate and sufficient food, shelter, water, and protection from feline predators will attract birds of all migratory preferences to your garden.
In general, native birds favor native plants: they evolved to depend on, and are best adapted to species native to our area. While there is considerable nuance in the native vs. exotic plant debate, including some ecological benefit from non-native species, incorporating many native species in your garden is a solid foundation for promoting good songbird habitat.
Plant species diversity is another important principle of wildlife friendly gardening. The more diverse the landscape, the more diverse the potential set of critters and wildlife you can attract. Because different plant species produce flowers and fruits at different times of the year, planting more species helps provide food sources for birds (and the insects birds eat) over a longer period of time.
Most songbirds feed on insects, fruits, and seeds. Insects like caterpillars are important sources of protein for developing nestlings. Oaks and black cherry (Prunus serotina), host many insects favored by birds, including vireos and warblers. Plants that produce fleshy fruits, such as beautyberry (Callicarpa americana), pokeweed (Phytolacca americana), blueberry (Vaccinum spp.), blackberry (Rubus spp.), and dogwood (Cornus florida) provide sugar-rich, high energy food vital for birds migrating in the fall. In an unused wooded area, you can even let poison ivy thrive, as it is an important part of the natural food web, and most other animals are not affected by the allergenic urushiol the plant produces. To provide food for overwintering birds, include species such as native asters (Aster spp.), goldenrod (Solidago spp.), orange coneflower (Rudbeckia fulgida), and native panicgrass (Panicum spp.). It’s important to let these species go to seed: don’t deadhead for maximum wildlife benefit.
Birds also vary in their habitat preferences, so when designing a bird-friendly garden, include a mix of low lying forbs and shrubs, small trees, and large trees with extensive canopies for a diverse vertical vegetative structure to provide birds cover and nesting sites. Evergreens like American holly (Ilex opaca) and eastern redcedar (Juniperus virginiana) provide both food and cover during the winter.
Fortunately, we are blessed with a lot of water in North Carolina, and birds can get much of their moisture requirements from the food and dew, but bird baths can be beneficial during droughts. Birdbaths should be 2-3 inches deep, have lips for perching, and be within about fifteen feet from vegetative cover.
Finally, keep your cats indoors! Cats (even well-fed) are responsible for millions of songbird deaths a year, and research shows bells do not help in alerting birds to their presence.
For more information about bird-friendly gardening, explore the excellent Managing Backyards and Other Urban Habitats for Birds publication from NC State Extension.
Matt Jones is Horticulture Agent for North Carolina Cooperative Extension in Chatham County.