How to Protect Your Lawn From Salt Damage This Winter

Every Iowa winter, the strip of grass along the driveway and the city sidewalk takes a beating. Plows push salty slush onto it, shovels pile salty snow on top of it, and by April it's often brown, thin or dead while the rest of the yard greens up. Iowa State University (ISU) Extension says trees, shrubs, perennials and turfgrasses are all susceptible to salt damage, and that excessive use of salt by homeowners can cause problems, not just road salt.

The good news: most of the damage around a house is preventable, and it starts with how you clear snow. Everything below comes from ISU Extension, the Iowa Stormwater Education Partnership, city public works pages and the U.S. EPA.

How salt hurts grass and plants

ISU Extension describes several ways de-icing salts injure plants:

• "Physiological drought." When salt levels in the soil are high, plants can't absorb enough water even when the soil is moist.
• Nutrient problems. High salt levels restrict how well roots take up essential nutrients.
• Toxic ions. Too much sodium and chloride in plant tissue is toxic to many plants.
• Damaged soil. High sodium levels damage soil structure.
• Burned foliage. Salt landing directly on plants can dehydrate the tissue. ISU notes salt spray from passing traffic is especially hard on evergreens.

For trees and shrubs, ISU lists symptoms such as stunted growth, scorched leaf edges, early fall color and twig dieback; on evergreens, yellow or brown needles. Salt that builds up over several years can cause a slow decline.

Choosing an ice melt

Not all de-icers are equal. Here's how ISU Extension compares the common ones:

ISU's overall advice: a mix of sand and salt at a ratio of 50:1 works effectively to make walking surfaces safer and causes less damage to plants.

Watch out for fertilizer as ice melt. The City of Davenport's sidewalk tips say to avoid fertilizers and products containing urea for de-icing: they perform poorly below 20 degrees, need higher application rates, and very little of the fertilizer stays on your lawn; most runs off to waterways. Davenport also suggests reading what a "green" product actually contains, not just the label claims.

New concrete? The City of Waukee notes that if you have new concrete, choosing alternatives to salt can help keep your sidewalk in good condition.

Use less: the shovel-first method

ISU Extension's prevention steps are simple:

1. Wait until the precipitation has ended, then remove as much snow and ice as you can.
2. Apply only enough de-icer to loosen the ice, then shovel off the loosened ice. ISU points out it takes much higher rates to completely melt ice and snow.
3. Don't over-apply. Use salt only where it's needed.
4. Mix salt with sand or kitty litter. Fifty pounds of sand to one pound of salt works effectively.
5. Don't pile salt-laden snow and ice around trees and shrubs. The same logic applies to your lawn: pile snow where melt-water won't soak into the grass you care about most.

The Iowa Stormwater Education Partnership's homeowner guide adds:

• Shovel, plow or snow blow first.
• Sweep up dry leftover product and put it back in the container.
• Use a hand spreader instead of tossing cups or handfuls.
• Use sand for traction during freezing rain or ice events.
• It cites Wisconsin's SaltWise program: a 12-ounce coffee mug of salt is enough for a 20-foot driveway or about 10 sidewalk squares.

Davenport's tips agree: throwing more salt on won't speed up melting, and limiting access to your home to one entrance means fewer surfaces to treat.

Why it matters beyond your yard

Salt doesn't stay on your driveway. The Iowa Stormwater Education Partnership says it washes into storm drains that feed directly into local waterways without filtration, and that monitoring in Iowa and neighboring states has found elevated chloride levels in streams. The U.S. EPA says too much salt in the environment is toxic and lethal to aquatic life, pollutes drinking water sources and damages infrastructure.

If you hire a snow removal company

Ask what de-icer they use, whether salting is automatic, and whether they can use less salt (or sand) near your lawn edges, landscaping and new concrete. Ask where they'll pile snow. Our guide to choosing a snow removal company has a full checklist.

Spring: flush the salt out

ISU Extension recommends that as soon as the ground thaws in early spring, you heavily water areas where salt accumulated over winter. A thorough soaking helps flush salt out of the root zone. If you can, change the drainage so winter runoff flows away from your plantings.

If grass along the walk or driveway is thin or dead after you flush it, plan to reseed. ISU's fall lawn care guidance says late summer (mid-August to mid-September) is the best time to seed cool-season lawns in Iowa; see our winter lawn prep guide for more of ISU's fall calendar.

Planting near the street

When you plant trees near busy streets, ISU suggests choosing salt-tolerant species. ISU lists bur oak, northern red oak, honeylocust, northern catalpa, Kentucky coffeetree, horse chestnut, mugo pine and eastern red-cedar as tolerant of salt in the soil, and sugar maple, American linden, Canadian hemlock and eastern white pine as sensitive.

Frequently asked questions

Does road salt kill grass?

It can. ISU Extension says turfgrasses are susceptible to salt damage. Salt in the soil creates a "physiological drought," limits nutrient uptake and can be toxic to plant tissue.

What ice melt is safest for lawns?

Per ISU, calcium magnesium acetate (CMA) causes little or no damage to landscape plants but costs much more. Sand or kitty litter doesn't melt ice but is not harmful to plants. A 50:1 sand-to-salt mix is ISU's practical middle ground.

How much salt should I use on my driveway?

Use only enough to loosen the ice after shoveling. The Iowa Stormwater Education Partnership cites a 12-ounce mug of salt for a 20-foot driveway or about 10 sidewalk squares.

Can I use fertilizer to melt ice?

The City of Davenport advises against fertilizers and urea products as de-icers: they work poorly below 20 degrees and mostly wash into waterways.

How do I fix salt damage on my lawn?

Heavily water salt-affected areas as soon as the ground thaws in spring to flush salt from the root zone, as ISU recommends, then reseed thin spots at the right time of year.