Types of De-Icing Products
Several ice melt products are available, some of which work better at lower temperatures than others and have different degrees of harmfulness to plants. The most popular ones contain different types of salts (chlorides). There are four main types, including sodium chloride, also known as rock salt. It’s inexpensive, but it only melts ice when temperatures are 12˚F or higher, and it doesn’t take much of it to damage plants, vehicles, and concrete. You may also see magnesium chloride ($15, The Home Depot), often marketed as pet-friendly and effective down to 5˚F. It can be a safe option when applied at about 1-2 pounds per 100 square feet. Potassium chloride (muriate of potash) is more commonly sold as fertilizer than a de-icing product. However, you may see it mixed with other chloride-based melting agents in de-icing products. It’s best not to use the fertilizer for de-icing because it’s easy to overdo it and damage your plants. The least harmful de-icing agent to the landscape is calcium chloride ($21, The Home Depot) which works at the lowest temperatures (down to -25˚F) of all the chloride-based products. Products containing calcium magnesium acetate aren’t chloride-based, are less corrosive to surfaces, and have low toxicity for plants, but they tend to be more expensive. This chemical is also only effective at melting ice in temperatures 20˚F or warmer. Whichever product you choose, always follow label directions to ensure you use the correct amount for the area you need to cover. Adding more than you need won’t get the job done any faster, and the less ice melt in the environment, the better for you, your plants, and your pets.
Minimizing Damage from De-Icing Products
If you’re only dealing with a few slick spots that are likely to melt away as temperatures rise during the day, you may be better off using coarse sand or another abrasive, such as sawdust ($7, Tractor Supply Co.) instead of a de-icing product. They’ll provide traction on slippery surfaces but won’t help melt ice. Or you can combine less than 5% of a de-icing product with a skid-proofing substance, such as sawdust, sand, kitty litter ($9, Target), fine gravel, or straw. One pound of de-icing salt mixed with 50 pounds of sand can be effective on walks and driveways without adding too much salt to the landscape. The salt helps melt the ice, while the other material will help keep a surface safe after the salt has dissolved. Stick with recommended amounts to minimize harmful effects on plants, concrete, and other surfaces. Another strategy when dealing with snow and ice is to avoid shoveling or piling treated snow onto your landscape as much as possible. When the weather warms, the thawing of the snow and winter rain can dilute salts and reduce accumulation in the soil, but if early spring weather is dry, rinse plants to eliminate residual salt and run irrigation to help flush salts from the ground. Sometimes salt spray from passing cars ends up on your landscape along a roadway. To protect sensitive turf or nearby plants, you can provide a barrier, such as burlap wrap or snow fencing. You can also select plants that are more salt tolerant. Species with hidden or submerged buds, thick surface wax, numerous and tightly arranged bud scales, fuzzy buds, or sticky resin-coated buds are more capable of protecting themselves from salt spray.
