Will Salt Damage My Landscape?

Will Salt Damage My Landscape?

Let’s put it this way. In ancient times, salt was used by armies as a biological weapon to destroy enemy’s fields and crops. So the short answer is yes, salt will damage landscape plants.

Salt is made from sodium chloride. It is very useful for melting snow and ice, and good as a seasoning on the dinner table. It can and does damage landscape plants as well as hardscape walkways, driveway and patios.

How Salt Damages My Landscape Plants

When a plant takes up sodium from salt, it dehydrates the roots, changes their physiology and causes additional plant stress. Meanwhile, roots absorb the chloride and transport it to the leaves where it accumulates and interferes with chlorophyll production and photosynthesis.

Salt damage does not stop at the roots. When passing vehicles spray salts on plants, it can damage the plant’s leaves, buds and small twigs. This can reduce the plants cold hardiness, making them more susceptible to freeze damage.

How Salt Damages My Hardscape

Concrete may look like a solid material but it is actually quite porous. Sodium chloride (rock salt) lowers the freezing point of water from 32 degrees down to 25 degrees. It will melt the snow and ice into water between 25 and 32 degrees. This water will soak into the concrete. Salt is also hydroscopic which means it actually attracts more water to it. When the salt/water mixture soaks into the concrete it is actually has around 10% more water than normal. When the temperatures fall below 25 degrees, this water in the concrete expands, causing the damage. Additionally, the more often the freeze/thaw cycle happens, the more likely the damage is to occur.

Is There A Safe Way To Melt Snow And Ice?

The good news is that there are materials available that will minimize the damage to both plants and hardscapes. One alternative is to use sand. The negative side of this is that it only provides traction, not melting, and it tends to get tracked into your home.

When possible, consider non-sodium de-icing agents such as calcium chloride or calcium magnesium acetate (CMA), a salt free melting agent made from limestone and acetic acid. Calcium chloride causes minimal damage to plants and lawns.

Calcium chloride is also the preferred ice melter for concrete. Calcium Chloride pellets are a fast acting product that melts ice and snow, and resists re-freezing to a temperature of –25 degrees, way colder than we typically get in Montgomery County. This protection to lower temperatures reduces the frequency and damage potential of the freeze/thaw cycles.

The local independent hardware stores, as well as Lowe’s and Home Depot, all carry Calcium Chloride products.