The Bay Gardener by Dr. Frank Gouin

Keep Your Grip in Snow and Ice without Harming Your Plants

Don’t use rock salt around your gardens

Old Man Winter has come to visit. As temperatures drop every year, ice slicks stairs, sidewalks and driveways, causing young and old to slip. To clear away these potential hazards, many people spread rock salt, either to ward off ice or to melt it away when already frozen. Rock salt is readily available and cheap. However, excessive salting around plants or where the water accumulates can damage plants.

Salt draws water out of plants, severely stunting or killing them, depending on its concentration. As a New Englander used to snowy winters, I’ve seen plenty of evidence of road salt at work in dead grass and stunted trees and shrubbery. In Maryland, where winters are usually milder, the evidence isn’t so clear, but road salt is still an extra stress that plants have to work to overcome.

To melt ice and keep your plants greener, use calcium chloride. Calcium is the salt you’d use for melting ice when making ice cream the old-fashion way. Calcium chloride will melt ice at a lower temperature than rock salt, or sodium chloride, which stops working when temperatures drop below 21 degrees. Calcium chloride will melt ice near 10 degrees. What’s more, the calcium doesn’t damage plants like sodium does.

Magnesium chloride is another safe deicer.

Never use fertilizers to melt ice, because fertilizers easily wash into the Chesapeake Bay, where nutrients are already causing major problems.

Never use automobile antifreeze; it’s toxic and can cause blindness if consumed by humans, animals or fish. Instead, take your used antifreeze to a recycling center.