Winter in Evanston can be rough. We all know that and we have found ways to survive it. If it is a collection of coats, hats, and scarves or an annual vacation to a warm location, we all have strategies to power through. One aspect of winter that we can’t get away from though is snow on sidewalks, driveways, and roads. It is estimated that we use about 137 pounds of salt per person in the US every year for de-icing. Soil up to 30 feet away from a heavily salted area has been detected to have salt concentrations up to 10 times the amount that will inhibit seed germination and root growth in some plants.
While plants will react differently depending on their salt sensitivity, one of the clearest symptoms of salt damage is asymmetrical damage—the side of the plant that is facing the road or sidewalk will likely show more damage. In evergreens this will be browning needles. Deciduous plants, however, are more difficult to diagnose. Damaged leaf buds will be slower to break dormancy, flower buds are likely to fail, but the other side of the plant will grow normally.
There are many ways you can protect your plants from salt damage:
Always shovel the snow off your sidewalks and driveway as soon as possible. This will prevent it becoming impacted and forming ice.
Use coarse sand instead of salt to provide traction
Use salt carefully, follow the instructions on the package
Consider alternatives to sodium chloride
Cover your salt sensitive plants with plastic or burlap to minimize their exposure to salt
On years when heavy salt use was needed, irrigate your soil prior to spring planting
For more information on salt toxicity, alternatives to sodium chloride, and a list of salt tolerant plants, look at https://www.extension.purdue.edu/extmedia/id/id-412-w.pdf