It's the perennial winter tug-of-war: How do you make snow- and ice-covered walkways safe while protecting your landscape from harmful deicers and road salt? Salt and other ice-removal compounds can be very hard on the grass and shrubbery adjacent to paved surfaces. There is a way, however, to walk this fine line of safety for people and plants alike.
Step 1: Understand the Effects of Road Salt
Sodium chloride (rock salt) is the most widely used ice-melter and is a corrosive. Over long periods of time, it can damage metal on cars and eat up concrete and asphalt surfaces—just imagine what it can do to your plants!
Salt is toxic to plants when it is absorbed into the water in soil, negating phosphorous and potassium, both of which are essential to a plant's survival. Salt dehydrates roots and makes the plant more susceptible to the cold. It also causes direct damage to leaves and other external parts of plants. The damage it causes also might not be apparent until months or even years after.
Step 2: Salt Less, Shovel More
Shovel snow and ice rather than use salt. The less rock salt you use, the better. It's usually the last thing people want to do, but the best remedy for removing snow and ice is shoveling. The longer you leave snow and ice on your driveway and walkway, the harder it will be to remove. With heavy snowfall it pays to start shoveling even as the snow is still falling. You might have to go back out to finish, but the shoveling will be easier if you do a few inches at a time. Make sure you have a good-quality, lightweight snow shovel. Metal shovels are easiest to use and have less chance of breaking. Remove snow from the driveway and all walkways needed for access to and from your house.
Don't forget to shovel around your mailbox, garbage cans and other areas you'll need to access.
Shovel snow toward where you'll be piling it so that you'll have less distance to toss it as you start to tire. Chip away any ice that you find under the snow with an ice chipper and remove it with the shovel. Push snow out of the way when and where possible. Only pile on as much snow as you can handle on your shovel. Don't overdo it, and don't bend with your back—always lift with your knees.
Shoveling snow and removing ice can be tiring, hard work. Be careful, especially if you are not physically fit. If you have medical or health issues, such as a heart condition, you should check with your doctor before doing this kind of work. Stay hydrated; as with exercising, drinking plenty of water is a necessity when shoveling.
Remember to dress appropriately by wearing layers. As you work, you'll warm up so shedding a layer or two will make work easier and more comfortable. Wear work gloves and snow boots as well.
Keep in mind that you're not in a race. You don't need to finish the job in one long shoveling session. It's best to work for 30 to 45 minutes and then go inside to warm up and rest for an hour or so. Then, when you're feeling up to it, head back out.
Step 3: Salt Sparingly
Use salt sparingly on paved surfaces that are not close to any kind of vegetation. Using more is not ideal since there will be a better chance of it escaping paved areas, making its way into your soil and being absorbed by your landscaping. Use the smallest amount possible and apply only when necessary. Try mixing it with sand to reduce the amount needed. A handful of rock salt goes a long way—one handful per square yard. Be sure to read and follow product instructions carefully.
If you haven't been able to keep up with the falling snow with your shovel, and the snow has turned into a slick, rock-hard layer of ice, you should use some kind of deicer or other material to ensure no one slips and falls. Whether, it's something that melts ice or just provides traction, safety is a priority during the winter.
When battling the snow with your shovel, be sure you don't shovel snow and ice that contains salt onto any of the surrounding vegetation.
Step 4: Use Something Else
Consider alternatives to using rock salt (sodium chloride). Two common deicers are calcium chloride and magnesium chloride. These two can still be toxic in high concentrations. The same rules with salt apply here: use these deicing compounds sparingly. Note that deicers with magnesium chloride may contain a cyanide derivative or potassium chloride, which can cause damage to your landscape.
Rock salt is limited by temperature. It only works at temperatures just below freezing. Anything colder than that and it is ineffective. Calcium chloride and magnesium chloride deicers work in very cold temperatures.
For the best selection, visit your local True Value® hardware store early in the season to get deicing compounds. If you wait until a big storm hits, you may not have many choices and will be forced to use rock salt.
Calcium magnesium acetate is the most environmentally safe product to remove ice. It won't corrode metals or cause significant harm to plant life. It is allegedly as corrosive as normal tap water and in varying concentrations can be effective against ice down to around -18°F.
Sand is another option that has been used for decades. While it doesn't necessarily melt snow and ice, it does provide traction on slippery surfaces. Because it's natural, it won't contaminate soil and lead to landscaping problems. The downside is it's not as effective as a deicer. Cat litter has also been used in the same way as sand to boost traction, but it can make a mess—you don't want to track it into the house.
Liquid deicers are beneficial in that they allow you to use less of the chemical and cover a greater area than solid pellet products. However, they are often more expensive.
Remember that deicers are not substitutes for shoveling and breaking up ice. They should be used as a means to make it easier to remove snow with a shovel.
Step 5: Take Protective Action
The best way to protect your landscape is to not use a deicer. However, in many regions this is not feasible. While you can personally control how much you use and where it goes on your walkways and driveways, it can be difficult to protect your lawn and plants from road salt on the outer perimeter of your property where municipal trucks spread salt on roads. The salt from roads often ends up splashed by vehicle traffic onto lawns and plants.
Consider putting up burlap screens, plastic fencing or snow fencing to protect flower beds from salt spray and snow build-up. You should also consider planting plants that are more salt-resistant, such as rugosa roses, potentilla or snowberry.
Step 6: Assess/Repair Any Damage
After a thaw, survey your landscape to see if you can see any spots where salt may have affected plant life. If feasible, water your lawn or flower beds adjacent to concrete surfaces to flush salt from leaves and soil. Or you can brush salt and snow off of plants with a broom, which will lessen any damage.
Good job! Now you should have a better handle on how to walk that line between plant protection and personal safety.
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