Why Plant Natives?

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Bringing Nature Home by Douglas Tallamy

You have probably noticed the growing movement (no pun intended) to garden with native plants—it’s hard to miss the myriad articles, programs, websites, and testimonials to its benefits. But why should we join this movement? While we’ve all noticed the steep decline in bees, butterflies, moths, lightning bugs, gnats, and other insects in recent years, and read about the need for these pollinators to protect our food supply, do we really understand how planting native will reverse this trend? 

In her excellent article in last month’s Gazette, Piedmont Master Gardener Angela Orebaugh presented a cogent argument for why we need pollinators—i.e., birds, bats, bees, butterflies, and moths. By pollinating plants, they make our abundant food supply possible, as well as helping flowering plants, which produce oxygen and remove carbon dioxide from the air. She provided a do-it-yourself guide to creating a pollinator garden, and included a handy list of native plants to get you started. A native plant is usually defined as one that grew here prior to European colonization, but this definition is a matter of debate. 

I hopped on the Plant Native bandwagon early, because I’ve always loved wildflowers and because all my friends were doing it. But I did not really understand WHY it is important to garden with native plants until I read the bible of the movement, Bringing Nature Home: How You Can Sustain Wildlife with Native Plants (2007/2009) by Douglas W. Tallamy. Tallamy is chair of the Department of Entomology and Wildlife Ecology at the University of Delaware, and has been researching and teaching about the relationship between plants and wildlife for 30 years. This book offers an additional key reason we need native plants: they feed native insects—including bees, beetles, dragonflies, lightning bugs, and caterpillars—which in turn feed other wildlife, such as birds, bats, turtles, spiders, and frogs. “Insects provide food either directly or indirectly for most other animals,” Tallamy explains. “Nearly all terrestrial birds rear their young on insects.”

The major revelation that enlightened me upon reading this book is that because they “coevolved” with native plants over millions of years, most insects can eat ONLY native plants. “Alien” plants, by contrast, are ornamentals from Europe and Asia imported by nurseries—including the many lovely species that routinely populate our gardens, such as forsythia, crape myrtle, and butterfly bush—some of which have become invasive. Because the leaf chemistry, shape, and developmental timing of alien plants taste bad to them, make them sick, or are not even recognized as food, “most native insects cannot, or will not, eat alien plants.” Ninety percent of our native insects—including the caterpillars that grow into our beloved butterflies—are “specialists,” meaning they require a native host plant in their life cycle. While butterflies will nectar on a whole range of native and alien flowers—such as zinnias, lantana, and marigolds—their caterpillar larvae can only feed on specific, native host plants. The monarch butterfly, whose caterpillar eats only the leaves of milkweed plants, is not—as I had previously assumed—the exception, but the rule—just one example of the vast majority of insect specialists. Fritillary larvae eat only the common violet, and larvae of the Eastern Tiger Swallowtail—Virginia’s state insect—eats only native trees such as black cherry, tulip poplar, and birches. The monarch was recently declared an endangered species by the International Union for the Conservation of Nature (IUCN), its population having declined 75% over the last 10 years and 95% since the 1990s.

The typical American suburban landscape of sterile, manicured lawns and pretty, alien shrubs represents a food desert for local wildlife. “Our native insects will not be able to survive on alien plant species,” Tallamy explains, because “if an insect’s hosts are not present, it won’t be either.” In Bringing Nature Home, Tallamy presents the strongest argument yet—backed by copious research evidence—that home gardeners can make a difference in sustaining our biodiversity by planting native as much as possible, and eliminating alien invasives such as autumn olive, English ivy, privet, and Japanese honeysuckle, which crowd out the natives. The book also provides an eye-opening list of the host plants for many butterflies and moths, as well as lists of recommended native trees, shrubs, grasses, ferns, and perennials for each region of the U.S. 

If you’re ready to get started, the Virginia Conservation Assistance Program (VCAP) from the Thomas Jefferson Soil & Water Conservation District offers modest grants for turning turf grass to native meadow—but you must apply before beginning the plantings.  

As Tallamy reminds us, “Because food for all animals starts with the energy harnessed by plants, the plants we grow in our gardens have the critical role of sustaining, directly or indirectly, all of the animals with which we share our living spaces. The degree to which the plants in our gardens succeed in this regard will determine the diversity and numbers of wildlife that can survive in managed landscapes.” The Plant Native movement represents a paradigm shift in the way we garden. “[Native plant] gardeners can and will ‘change the world,’ he continues, “by changing what food is available for their local wildlife.” Of course, we can still plant our favorite non-natives, but we should try to strike a balance. I have peonies and weigela alongside the false indigo and swamp rose mallow. 

One fun and easy way to join the Plant Native movement is via Tallamy’s Homegrown National Park project, “catalyzing a collective effort of individual homeowners, … farmers, and anyone with some soil to plant in…to start a new HABITat by planting native plants and removing most invasive plants” (homegrownnationalpark.org). Once you’ve started planting natives, you can “get on the map” by registering how much land you have devoted to native plantings, no matter how small. The national goal is 20 million acres; Virginia boasts 1,979 acres so far, 1.25 acres of which are in the 22932 zip code. 

Finding native plants to buy is challenging, but getting easier as demand grows. The Piedmont Master Gardeners has recently provided stickers to our local nurseries to identify the native plants they carry. Hummingbird Hill Native Plant Nursery in Free Union will consult with you to recommend and sell you the native plants suitable for your specific ecosystem (hummingbirdhillnatives.com). The National Wildlife Federation’s Garden for Wildlife sells native plants online by state (gardenforwildlife.com/collections/native-plants-for-virginia). The Joyful Butterfly in South Carolina sells both host and nectar plants and seeds for butterflies, including all varieties of milkweed (joyfulbutterfly.com).

Edible Landscaping in Afton sells food plants, many of which are native, such as pawpaw and persimmon (ediblelandscaping.com). And every spring, watch for the wonderful local plant sales offered by Monticello, the Virginia Native Plants Society, and Piedmont Master Gardeners.

Resources for Choosing and Identifying Native Plants:

  • Flora of Virginia—book for $90 or app for $20
    Piedmont Native Plants: a Guide for Landscapes and Gardens (2015, 2019) $15 from www.vnps.org
  • The Seek app by iNaturalist 
  • Virginia Native Plant Society www.vnps.org (includes a list of native plant nurseries)
  • Piedmont Master Gardeners piedmontmastergardeners.org/gardening-questions/native-plants/
  • Plant Virginia Natives www.plantvirginianatives.org, and 
  • Va. Dept. of Conservation & Recreation www.dcr.virginia.gov/natural-heritage/nativeplants Digital Atlas of the Virginia Flora www.vaplantatlas.org 
  • Audubon Society’s Native Plants Database www.audubon.org/native-plants, where you can search by zip code. 
  • And every spring, watch for the wonderful local plant sales offered by Monticello, the Virginia Native Plants Society, and Piedmont Master Gardeners. 

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