Salt damage to lawns and plants is a relatively common problem where salt is used on sidewalks and streets during winter months. Salt damages plants in two ways.
- First, salt and salt spray can burn grass, hedges and other plants when it comes in direct contact with them.
- Second, salt, when it gets into the soil, can impede water and nutrient intake. So plants can suffer drought conditions even if get water and starve even if the soil contains adequate nutrients.
So what can be done to mitigate salt damage to lawns and trees? Well, there are a few things that can help.
- First, as always, prevention is the best solution. In other words, you need to find ways to prevent the salt and salt spray from becoming a problem in the first place.
- Shifting from a de-icing compound high in sodium chloride to one higher in non-harmful materials, such as sand, for example, is probably the best thing you can do. Work on both fronts. Try to get people in authority in your city or town to make the change, and put your money where your mouth is by switching to less harmful compounds. Sand or fine gravel mixed in with salt can be an efficient compound.
- For hedges and other sensitive plants, use burlap. As a barrier, it will stop any salt being thrown at your plants, by road maintenance equipment, for instance, and absorb any salt spray generated by traffic.
- For your grass lawn, you can use turf covers. These must be permeable to air and water, but they must be much thicker and resistant than burlap. They will not offer complete salt protection, but they will certainly help.
- Using a bit of pelletized gypsum in the fall may also help deal with some of the salt that gets absorbed into the soil.
- But, if you realize, when the sun starts to shine and the tulips come up, that a strip of turf grass adjacent to the sidewalk has turned yellow, or that part of your cedar hedge seems burnt and dried out, you need to do work on fixing the damage.
- First thing is to try to get rid of as much salt as possible. If the spring is particularly wet, nature will be on your side, and a large part of the salt may be washed away naturally. If, unfortunately, you don’t get a lot of rain, you will have to do mother nature’s job. The water will dilute the salt and make it sink deeper into the ground.
- If you didn’t use pelletized gypsum in the fall, you could use some now. Gypsum makes soil more permeable, which helps water drainage, which can make the salt wash away faster. It can help your plants and turf grass get the nutrients they need.
- You should know that success may take time and is in no way guaranteed. A damaged hedge may take months, if not years, to start looking its best again.
- Soil that has been salted year after year may need to be replaced by fresh, clean soil. If you tried fixing your salt damaged turf or plants last year and got very poor results, it may be a sign that a more drastic approach is needed.
If you don’t manage to make things better, or if you just don’t want to try to save the turf or plants you currently have, the alternative is to replace them. A word of advice: choose plants that are more tolerant to salt damage. For information on this, have a look at the following:
- For turf grass varieties that are less sensitive to salt: Salt-Tolerant Roadside Grasses: Does Anything Actually Survive? (from the University of Minnesota)
- For plant varieties that are less sensitive to salt: The Impact of Salts on Plants and How to Reduce Plant Injury from Winter Salt Applications (from the University of Massachusetts)