The Midwestern Native Garden. Charlotte Adelman
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native plants, we can avoid invasive plant species . . . that harm natural areas.”22 For those who wish to avoid planting a potentially invasive nonnative plant, the Brooklyn Botanic Garden says, “the most prudent prevention measure is to choose a regionally native species.”23
Studies show that “most of the ornamental species in parks and gardens are alien, e.g., lawn grasses, rose bushes, lilacs. Therefore, with as many as . . . one-third of the species in the flora foreign, they dominate the visual impact of the flora in much of middle North America.”24 How did this begin? European settlers in North America felt threatened by the vast wilderness, and they missed their familiar, back-home shrubs, trees, and flowers. Because the native flowers were so plentiful, pioneers called them “common” or “weeds,” unflattering names that persist to this day. To satisfy their customers, colonial nurseries imported European plants, beginning the long-term trend of importing ornamentals. But today’s gardeners have the information, desire, and ability to reverse yesterday’s habits now that a wide selection of beautiful native plants and wildflowers is conveniently available from reliable commercial sources.
We’ve examined a range of well-documented reasons that Midwest gardeners are inspired to choose regionally native plants. Regardless of the motives that resonate with you most, we offer some great native choices within this book. For the best results, go at your own pace. Go beyond our suggestions. Develop your own ideas based on your research and observations. Extend the concept of replacing nonnative plants with natives to include nonnative trees and shrubs, window box plantings, rooftop gardens, and all planters. Share native plants with your friends and neighbors. Collect native-plant nursery catalogs and spend time dreaming about beautiful native plants and flowers, rather than the nonnative varieties. For landscapes and gardens large and small, our book can serve as a handy guide for choosing native midwestern flowers and plants.
Environmental Reminder
Removing native plants from their natural environments increases their vulnerability. Removal also decreases survival chances for the beneficial insects, including butterflies, skippers, and bees, that depend on native plants for survival. Patronizing native purveyors (see “Selected Resources” in the bibliography) and sharing native plant bounty among friends, relatives, and neighbors are responsible ways to acquire native plants.
1
SPRING
“The winter wind has lost much of its cutting edge,” wrote naturalist John Madson about the midwestern spring. “From then until hard frost, there will be no time when the prairiescape is not enameled with flowers of some kind. From the first pasqueflowers of March to the towering sunflowers of October, the tallgrass prairie will never be without flowers.”1 March brings the first pasqueflowers, but for another twentieth-century nature lover, Patricia Duncan, “the month of May is the apex of the spring prairie. Green is taking over, bird song is taking over, and insects are taking over. Wildflowers such as golden alexanders, birdsfoot violets, prairie rose, spiderwort, purple milkweed . . . are taking over.”2 Midwestern spring flowers had nineteenth-century admirers, too. “The earth in the woods is covered with May-apples not yet ripe, and in the enclosed prairies with large fine strawberries, now in their perfection.” Also beautiful are “the red lily, and the painted cup, a large scarlet flower,”3 wrote William Cullen Bryant. Visiting Illinois to be with her sister, Eliza W. Farnham wrote, “The landscape grows more beautiful every day. The prairie puts on its richest garb about the first of June. The painted cup, moccasin flower, and geranium, come out.”4 Observing spring while touring the Great Lakes in 1843, Sarah Margaret Fuller wrote, “In the wood grew not only the flowers I had before seen, and wealth of tall wild roses, but the splendid blue spiderwort, that ornament of our gardens,” and the “most delicate flowers,” including “a familiar love, the Scottish harebell, the gentlest, and most touching form of the flower-world.”5
After our long winters, midwesterners look forward to beautiful spring flowers. It’s too bad that many commercial garden centers, catalogs, and public displays of spring flowers feature ornamental plants from Europe and elsewhere. Native spring flowers are just as beautiful, and their nectar attracts bees and butterflies. Midwestern wildflowers also play an essential role in butterfly reproduction, because these insects lay their eggs only on host plants that the caterpillars, or larvae, can digest, which most often are native plants. Several fritillary butterfly species lay their eggs on or near native violets, sometimes when the host plant has already dried up. The parsnip, or black swallowtail, butterfly (Papilo polyxenes) and the Missouri or Ozark woodland swallowtail butterfly (P. joanae) lay their eggs on plants of the Carrot family, such as spring’s golden alexanders (Zizia spp.). America’s best-known butterfly, the milkweed or monarch butterfly (Danaus plexippus), lays her eggs on milkweeds (Asclepias spp.); the spring bloomers among them include blunt-leaved, green comet, and purple milkweed. As is typical of more than 90 percent of insects, most butterflies are restricted in their diets to native plants, because they “have not developed the enzymes” required to digest the leaves of nonnative plants.6
American redstart (Setophaga ruticilla)
Yellow warbler (Dendroica petechia)
Common yellowthroat (Geothlypis trichas)
The Midwest’s spectacular show of native spring flowers coincides with another extraordinary regional event. As northern birds, like the juncos (p. 207) that spend the winter in the Midwest, depart north for the summer, tiny, gorgeously colored warblers, robins, native sparrows, woodpeckers, and hummingbirds fly in by the millions from winter homes as far away as South America. At the end of their long journeys, the migratory birds begin to reproduce and seek tiny insects and caterpillars to feed their young, as do cardinals, chickadees, and other year-round residents. For birds, the native spring flowers play an essential role: hosting a variety of insect caterpillars and attracting quantities of tiny insects.
Many early spring flowers are ephemeral, so they take advantage of available sunlight before it is blocked by leafed-out plants. This brief window of opportunity attracts pollinators. Frequent visitors include various bee species, some just emerging from their underground wintering quarters. Some bees, such as honeybees and bumblebees, are generalists. Others, like the tiny, solitary bees called oligoleges, are specialists. Codependency requires these insects to pollinate specific species/genera of flowers. If a population of specialist bees fails to locate its special flowers, it cannot survive. The loss of one native bee population puts existing clumps of the beedependent flowers at risk.
Many insects contribute to the spring insect tapestry, but for native plants, none are more important than the ants. Wild ginger, blue cohosh, goldenseal, twinleaf, bloodroot, and trillium are some of the many native woodland spring flowers that depend on ants to distribute their seeds, and not on wind (as do some flowers and most grasses), because trees block the wind. The ants are attracted to the plant seed’s edible fleshy protein-rich appendages, or elaiosomes, which they carry to their nests to eat later. “After the ants have consumed the elaiosomes, they take the seeds to their waste disposal site, and ‘plant’ them in this nutrient rich environment.”7 Ants have been observed carrying wildflower seeds 30 feet away from a plant.8 Like bees, ants are an example of codependence, which benefits both parties and has existed since time immemorial. Wasps and mammals also perform this vital seed dispersing. Introduced nonnative ants may enter into or disrupt these mutualistic interactions between numerous