Winter is in full swing, and with it the challenge of keeping walkways clear of snow and ice. Whenever salts or other de-icing chemicals are used to assist in the ice removal, special caution should be taken to reduce the damage these agents can cause to the surrounding vegetation. Salts are toxic to plants when they dissolve in water because sodium ions replace the phosphorous and potassium in the soil. Rock salt also absorbs the water in the soil, taking it from the roots. This causes stress and dehydration for the roots of surrounding foliage. Salt also reduces the cold hardiness of plants making them even more susceptible to frost damage.
The biggest problem with using ice melts is that people generally think ice melt should be used on top of the ice to melt it away, but it doesn’t quite work that way. Ice melting products work by preventing, or at least reducing, the ice right on top of the hard surface of the ground, making it easier to shovel and remove the ice. It’s best to apply before it begins to snow or freeze, and to stay on top of the shoveling so no ice or snow can really accumulate.
To help minimize the damage salts can cause to vegetation, it’s important to keep a few things in mind:
Don’t overuse. Follow the manufacturers’ recommendations exactly.
Don’t use rock salt in extreme cold. Rock salt only works down to about 15 degrees. If it’s any colder than this, it will freeze anyway.
In extreme cold, use chemicals like calcium-chloride or calcium magnesium acetate to prevent the buildup of ice.
Apply the de-icing product before it begins to precipitate. It’s easier to keep ice off than it is to remove it after it accumulates.
Shovel walkways as soon as possible after a storm. During some large storms, you may consider removing the snow several times instead of all at once.
Brush or otherwise knock any stray chemicals off of plants.
Erect simple barriers to protect delicate plants. This can be as simple as burlap rolled up into a berm.
To reduce the amount of chemical needed, try using sand or kitty litter on the surface of the ice to increase traction while the ice melts naturally
Take extra care to apply chemicals to sidewalks, other walkways, driveways, etc without overspreading to adjacent areas.
Ensure proper grading to encourage the salts to run to specific locations, vegetation free, instead of your flower beds.
Whatever you use, and where ever it is used, use less. Start small and if needed, apply more.
Try using liquid ice melts. These are fairly new and may not be readily available in your area, but keep an eye out. These are much easier to apply and use fewer chemical.
Remember that safety is the driving force to remove the ice in the first place. While we should try to protect vegetation as much as feasible, grass can be replaced much easier than a hip after a bad slip and fall. Use de-icing chemicals sparingly, but use as needed.