As if a short growing season, tornadoes and a hot, humid summer weren't enough, Wisconsin gardeners also have to deal with lots of hungry critters, the largest of which are deer. Even urban gardeners need to familiarize themselves with deer-resistant plants if they want healthy landscape or plentiful harvest in Wisconsin.
Deer and the Landscape
Deer lived in Wisconsin before residential landscaping began. Early settlers removed deer's natural predators, wolves, and then created thousands of acres of cultivated pastures, making grazing a breeze instead of a challenge. The resulting expanding herds pushed out of rural woodlands into urban areas. According to the Wisconsin Humane Society (headquartered in Milwaukee where deer threaten city garden plots), fences, strobe lights, strips of mylar, noise and chemical repellents can make a backyard less attractive, but hungry deer will eat anything when desperate. They recommend the use of aromatic herbs like garlic, chives, onion, lavender, sage, honeybush and thyme to discourage deer from grazing urban and suburban gardens. Deer also dislike catnip and spearmint, but these members of the menthe family can be invasive and should be kept under control. Daffodils and chrysanthemums are flowers that few animals, including rodents, will eat; perennial oriental poppies and annual zinnias are popular Wisconsin garden flowers that deer dislike. Bottle brush, rhododendron and wild lilac are deer-resistant shrubs. Evergreen Douglas fir and blue spruce are deer-resistant trees.
Deer and Native Plants
Home vegetable and flower gardens and the trees and shrubs that surround them offer well-fertilized, well-watered, convenient grazing for deer. Native plants survive on less, so they offer a less lavish meal. Black-eyed Susan, purple and prairie coneflowers, Eastern red columbine, butterflyweed, golden tickseed, yarrows and spiderwort are native perennial flowers that deer find distasteful. Deer will also avoid wild bergamot, thistles and prairie goldenrod but these are aggressive growers that must be contained; many municipalities deem thistles and goldenrod "noxious," or invasive, weeds whose cultivation is illegal. Property owners who have wetland areas or ponds in their landscapes might consider Virginia iris, American lotus, cardinal flower and American eelgrass; deer may not be tempted to nibble while they drink. Junipers are uncomfortable in the mouth and deer palates are not fond of honeysuckle or chokeberry shrubs. The Lady Bird Johnson Wildflower Center has these and more suggestions for the gardener who wants to use deer-resistant native plants.
Small greenhouses and nurseries dot the Wisconsin country side; many owned by accomplished horticulturists or experienced staff. From Winter, a town in the far northern part of the state where the bears may outnumber the people and the deer outnumber both, the greenhouse-keeper suggests tiger lilies, peonies, heather, lupines, blanketflower and moss pinks perennials as some of the most deer-resistant perennials. Wax begonias, coleus, salvias, marigolds, nasturtiums and all morning glories are good annual choices. In spring, when leaves and branches are most tender, surround burgeoning plants with lily of the valley, grape hyacinth, winter aconite, glory-of-the-snow, common snowdrop, Siberian squill and spreading spirea shrubs. Wisconsin favorites like trumpet vine, Dutchman's pipe and potentillas are survivors; Northern catalpa, ash, larch and Gingko trees stand a good chance of escaping serious damage. Rugosa roses and all barberry bushes are too prickly for deer to love.