Winters in Dakota County can be freezing cold, snowy, and windy. These conditions require sidewalk shoveling, driveway snow-blowing, manual ice scraping and street plowing up to and including applications of deicer products. Your diligent clearing of snow and ice may minimize the amount of deicer spread across sidewalks, and driveways during the course of winter. Remember also, that as the ice and snow melts, the salts will run-off into the garden and impact garden plants roots. 

Many Minnesota plants are sensitive to road salt, which can cause dehydration, nutrient deficiencies, and eventual death due to both salt spray on foliage and salt accumulation in the soil. Evergreens are particularly vulnerable. 

The composition of deicer products varies depending upon requirements of the area. The primary difference is that "road salt" typically refers to raw, inexpensive rock salt for large-scale use, think streets and highways. While "sidewalk salt" (or "ice melt") often includes blends of different chemicals such as calcium chloride or magnesium chloride which are more effective in colder temperatures and can be less damaging to surfaces and plants. 

You can minimize the negative effects of deicer products on the plants in your garden by understanding which plants are better able to tolerate the chemicals. Choice of plant type and placement augments the plant’s innate ability to tolerate deicers salts. 

Here is information about plants that are and are not tolerant to deicers. 

Native Minnesota trees and shrubs that are sensitive to road salt include: 

Maples (Red maple, Silver maple, Sugar maple); Dogwoods (Grey dogwood, Red-osier dogwood, Red twig dogwood); Basswood (American basswood, Littleleaf linden); Pines (Eastern white pine, Red pine, Scots pine); and Firs (Balsam fir, Concolor fir).

Meanwhile, other Minnesota plants, including trees, shrubs, and perennials, are tolerant of road salt and are excellent choices for landscaping near roads, driveways, and sidewalks. Deciduous plants are generally more salt-tolerant than evergreens as they shed their leaves annually. These include trees such as: Oaks (Bur, Northern Red, and Swamp White); Hackberry; Honey Locust; Kentucky Coffee tree; River Birch; Serviceberry and Eastern red cedar. Along with shrubs: Sumacs (Staghorn & Smooth); Chokeberry; Winterberry; Lilacs; Viburnums (Viburnum spp.); Junipers (Juniperus spp.); Potentilla; and Rose (Rosa rugosa).

Additionally, the following grasses, perennials and wildflowers are effective at handling both salt spray and soil accumulation and are excellent for boulevard gardens.  Grasses: Little Bluestem; Big Bluestem; Switchgrass; Prairie Dropseed; Perennials and Wildflowers: Black-Eyed Susan; Purple Coneflower; Goldenrod; Asters; Butterfly Milkweed; Catmint; Sedums; Daylilies; and Yarrow.

For specific recommendations on seed mixes for different applications, the Minnesota Stormwater Manual provides detailed guidance. From quick facts about managing deicing products to in depth area management are available here:

https://extension.umn.edu/lawns-and-landscapes/effects-deicing-salts-landscapes

Photo Credits: University of Minnesota Extension (1,3), Missouri Botanical Garden (2)