Volume 14, Issue 51 ~ December 21 - December 28, 2006

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

It’s been a warm week, but soon we’ll see Old Man Winter appear. As temperatures drop every year, ice slicks stairs, sidewalks and driveways, causing young and old to slip. To clear away these potential hazards, homeowners often spread rock salt, either to ward off ice or to melt it away when already frozen. We often use rock salt because it is readily available and cheap. However, excessive use of it around plants or where the water tends to accumulate causes plant damage.

Salt draws water out of our 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 Fahrenheit. Calcium chloride will melt ice near 10 degrees. What’s more, the calcium doesn’t damage plants like sodium does.

Another safe deicer to use on the ground is magnesium chloride.

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.

Ask Dr. Gouin your questions at [email protected]. All questions will appear in Bay Weekly. Please include your name and address.

© COPYRIGHT 2004 by New Bay Enterprises, Inc. All rights reserved.