‘Tis the season of snowy winter wonderlands that melt and refreeze before long, transforming into treacherous ice that coats walkways, driveways and sidewalks. To prevent their families from slipping and falling, many people put down a common solution: rock salt.
Deicers lower the freezing point of water to prevent ice from forming. Rock salt, officially known as sodium chloride, is one of the most widely used deicers, in part because it is effective, economical and easily stored. However, it is also incredibly toxic to pets and plants and corrodes metal and concrete.
Even slightly safer solutions, such as calcium chloride, magnesium chloride, potassium chloride or calcium magnesium acetate can still be harmful to plants, while other deicing products such as urea deplete oxygen from waterways and are a serious danger to aquatic life.
County and city usage of rock salt on roadways is widespread, often applied as a brine to road surfaces prior to snowstorms to allow the saline solution to turn snowfall into slush. Rock salt applied in solid form post-snowfall prevents any existing snow from melting and refreezing onto roadways. The ensuing salty slush on the roads then gets sprayed by passing cars onto plants and lawns, often resulting in damage to affected areas.
Why are chemical deicers bad for lawns?
Deicers can stunt new plant growth, damage existing growth and even starve the plant of necessary water and nutrients if absorbed through the soil. Lawns, shrubs, trees and garden plants alike exhibit burned and dead areas when coated with salt.
Even worse is when rain and/or runoff deposits the salt into your yard and planting beds. Salt not yet dissolved into the soil absorbs water and can cause severe root dehydration for months. Once dissolved, the sodium and chloride ions are absorbed up into the grass or other plant through the roots instead of key nutrients, causing browning, dieback and even plant death. It will make your grass more susceptible to dying from winter weather, affect active root growth come spring and will exacerbate lawn and plant withering during droughts.
How can I limit lawn and plant damage from deicers?
If you put deicer down in anticipation of snowfall, do not remove the tainted snow onto your lawn when you shovel it away! If you instead tend to use rock salt after you’ve shoveled, be thorough in your snow removal efforts. The less salt-based deicing agent you need to put down, the less likely your lawn and plants could suffer damage. As the salty slush gets sprayed by passing cars, tracked everywhere by boots or flow into your yard with the next rains, it can spell catastrophe for your roadside plants and lawns.
When you do decide to spread deicers, always be sure to carefully follow label instructions for proper usage. You can reduce the amount of deicer needed by mixing it with kitty litter or sand to improve traction. We also recommend sweeping up and properly disposing of any residual salt after the snow and slush has melted and the ground surfaces are dry.
In summary, use chemical deicers sparingly and only as needed, otherwise your lawn and plants could suffer later.