GARDENING Return of the natives By Sally Cunningham Veronia (ironweed) is native to Western New York; Photo by Sally Cunningham. Native plants were here before we were, but the topic can still start serious arguments among horticultural professionals, botanists, and even gentle gardeners. Folks get quite worked up about what’s really “native.” (Are they only the plants that were here before Europeans arrived—or should we count the wildflowers and trees that have naturalized over decades? Must they be indigenous locally—or simply native to North America?) Others have heated opinions that we must use only “species” plants, rather than newer cultivars of native species. Some people write off natives, thinking they’re just messy and unkempt—Who wants the yard to look like an abandoned field, anyway? And there are those who figure it’s just another trendy fad from the “green” movement. So let’s take a closer look at the issue as it involves both city and country landscapes, and see what will really work for you. First, some definitions Native or indigenous plants: Among most scientists and horticulturists, the terms refer to plants that grew in North America before Europeans first arrived. Plants that came with settlers—on purpose or accidentally—often naturalized, and are called alien or nonnative species. For example, orange daylilies (hemerocallis fulva) and Queen Anne’s lace (Daucus carota or wild carrot) are nonnatives that are here to stay. The problem plants that have naturalized, causing ecological and economic trouble, are called nonnative invasive species, sometimes shorted to “N.I.S.” They might be only about three percent of the plants that have entered our fields and forests, but their impact is huge and terrible. (Ironically, even some North American native plants have joined the N.I.S. lists of some states. Black locusts, for instance are native in southern regions but invasive in New York State.) Even for us optimists and idealists, it’s unrealistic to expect gardeners and landscapers to go back to pure native plant gardening on a large scale. At least ninety-three percent of the plants we use in American yards are nonnative, and most of them don’t cause problems. Besides, what gardener wants to miss out on the excitement of new plant introductions—a hardier lavender, a bigger or tinier hosta, and better or longer-lasting flowers on hybridized annuals, perennials, shrubs, or trees? Not me, and probably not you. Yet there are important reasons to use native plants and many times when we could opt for one that is just as showy and as fine a performer as the hottest alien. As gardeners, nursery people, or landscapers, we may just need a bit more incentive to use them and knowledge about which ones fill the bill. Why use natives? The longstanding line has been that they are best suited to local conditions, including soil, precipitation, temperatures, and so on. It’s also often taught that natives attract fewer pests and diseases. The trouble with both statements is that they’re not always true. Many nonnative plants are even more disease-free than the native of the same species. (For instance, the native dogwood, Cornus florida, is particularly susceptible to the anthracnose disease, whereas Kousa dogwood is not.) As for suiting local conditions, that totally depends upon whether we actually provide the soil and microclimate the plant needs—same as for any plant. Our native trillium, Jack-in-the-pulpit, or hemlock isn’t going to be any happier than a Japanese maple, given the wrong soil texture or pH, sunlight, or drainage. Plants in our yards and gardens are mostly in an unnatural situation anyway; why would a native be all that comfortable? So the pest-proof and suit-the-site arguments are just not enough. But there is an important—even crucial—reason to use native plants as much as possible. It’s all about the insects My landscaping palette was turned upside down last year when I read a book called Bringing Nature Home: How Native Plants Sustain Wildlife in Our Gardens (Timber Press, 2007), by professor Douglas Tallamy of the Department of Entomology and Wildlife Ecology at the University of Delaware. I experienced a big “aha” that I share with you in the hope that you will start using more natives—even, or especially, in the suburbs and city. This is the simple version of Tallamy’s key points: 1. A land without insects is a land without higher forms of life; the food web depends upon insects. 2. Insects that eat plants (herbivores) can mostly eat only the plants with which they evolved. That is, our plant-eating insects must have native plants to eat. 3. Native plants in the wild are increasingly endangered or difficult to find. That’s because natural habitat is rapidly disappearing thanks to development (sprawl) and invasive plant species taking over. We can’t solve all the problems by backyard gardening efforts (issues like habitat fragmentation beyond the homeowner’s control), but we can collectively make a difference. The numbers are astonishing, and they leave Tallamy with this conclusion: “It is up to us, in the suburbs or cities, to protect or replace native plants in whatever ways we can—at the very least by using native plants on our own small plots.” Do you see a problem here, though? If I’m telling you that we need to use native plants to feed the native insects, will you have a yard riddled with tattered plants? Well, truth is—we should see a few holes in leaves because some caterpillars love the spicebush (Lindera benzoin) or the shrubby dogwood. (Remember, caterpillars become butterflies!) But I can assure you that native planting will not mean a raggedy garden. The reason? In a balanced, naturalistic backyard, just as in the woods, complex systems far beyond our own provide predators for everything. Parasitoid (nonstinging, often very tiny) wasps help control caterpillars, birds eat beetles, and so on. We gardeners aim for a balance between predators and prey—not always easy, but well worth the effort at orchestration. What about cultivars? Purists argue for using the species (the original natural form of a plant), rather than a cultivar (the hybridized, cultivated, form produced by human crosses). In a few cases it’s a good argument because sometimes the cultivar is “improved” in ways that don’t suit the native birds or butterflies at all. Some crabapples suddenly have fruits so big the birds can’t eat them; new annuals have nearly no pollen or nectar; or elderberry cultivars have great new colors of leaves but hardly any fruit at all. On the other hand, remember those plant-eating insects that so much else depends upon. The basic genetics—the DNA that made the leaves of those crabapples or elderberries suitable for the insects’ dinners—remains the same. The cultivars of bee balm (Monarda) and lindens (Tilia) are still bee balms and lindens to the bug, caterpillar, beetle, or fly. So yes, for most purposes, it’s still worthwhile and valid to use the cultivars of native plants. The songbirds that eat the beetles and the hawk that eats the birds will still thank you. Sally Cunningham is a horticultural professional. Native plants for home gardens Some native plants rise above the rest for their value and beauty in the home landscape. Remember, every plant has specific soil, site, and care requirements—so buy any plant only if you have or can create an appropriate setting. If you do so, the following will please you and contribute to a healthier ecological landscape. They are only some of the native plants you will find in WNY garden centers and nurseries. You may be surprised at how many you have been using already. —S.C. Perennials: Amsonia tabernaemontana, hubrichtii (bluestars) Anemone canadensis, A. virginiana (spring anemones) Aruncus dioicus (goatsbeard) Cheone glabra, C. obliqua (turtlehead) Cimicifuga racemosa (Actaea racemosa is the current name; also called bugbane, black cohosh, or snakeroot) Dicentra eximia (bleeding heart) Eupatorium dubium, E. fistulum (Joe Pye weed) Filipendula rubra (Queen of the prairie) Heliopsis helianthoides Hibiscus moscheutos, var. palustris and cultivars (hardy hibiscus) Oenothera spp. (evening primrose, Missouri primrose) Osmunda (cinnamon fern) and several ferns Polemonium reptans (Jacob’s ladder) Polygonatum commutatum (Solomon’s seal) Thalictrum spp. (meadow rue) Tiarella cordifolia (foamflower) Tradescantia virginiana and hybrids (spiderworts) Veronicastrum (Culver’s root) Vernonia (New York ironweed) Shrubs and small trees: Amelanchier spp. (serviceberry or shadbush) Aronia melanocarpa (black chokeberry) Betula nigra (river birch) Cephalanthus occidentalis (buttonbush) Cercis canadensis (eastern redbud) Chionanthus virginicas (white fringetree) Clethra alnifolia (summersweet, sweet pepperbush) Cornus spp. (silky dogwood, gray dogwood, red osier dogwood) Crataegus (hawthorn) Gaultheria procumbens (winterberry) Hamamelis virginiana (witch hazel) Hydrangea arborescens, H. quercifolia (smooth and oakleaf hydrangeas) Hypericum densiflorum (St. John’s wort) Ilex decidua (possumhaw) Ilex glabra (Inkberry), I. laevigata (smooth winterberry), I. verticillata (winterberry holly) Itea virginica (Virginia sweetspire) Lindera benzoin (spicebush) Maclura pomifera (osage orange) Magnolia virginiana, M. acuminata (sweetbay and cucumbertree magnolia) Mahonia aquifolium (Oregon grape) Myrica or Morella pensylvanica (bayberry) Philadelphus grandiflorus (mock orange) Potentilla fruticosa (bush cinquefoil) Physocarpus opulifolius (ninebark) Rhododendron (azalea, rhododendron—some species) Rhus (sumac—all species) Ribes sanguineum (flowering currant) Salix discolor, S. caprea, other spp. (pussy wilows) Sambucus (elderberry—all) Stewartia ovata (stewartia) Symphoricarpos albus (common snowberry) Vaccinium spp. (blueberry) Viburnums: V. acerifolium (mapleleaf arrowwood), cassinoides (witherod), dentatum (southern arrowwood), prunifolium (black haw), lentago (nannyberry), and nudum Vitex agnuscastus (chaste tree) SUBSCRIBE NOW Back to the Table of Contents Back to Top