Salt-tolerant plants that will survive in road-salt-laced soil

Each year, in late autumn, I’m awoken in the middle of the night by a giant thump, followed by shovelling noises. It’s the annual delivery of a giant yellow bin filled with road salt. I appreciate my municipality’s foresight and dedication, I do. I live on a hill, on the edge of a steep cul-de-sac and things get slick. In the absence of an alternative, it’s necessary. But inevitably, all that road salt gets washed into our storm drains and onto our properties. I have a garden right at the curb, so it gets a good dousing every time a plow goes by, scraping up what’s been spread onto the road. This got me thinking about salt-tolerant plants.

Some things have thrived in that little garden, but others have literally shrivelled up and died. Was it because of too much salt? I’ve tried to amend the soil, but it’s still pretty hard-packed and unforgiving.

A recent press release put out by the Soil Science Society of America about soils in winter led me to dig around on their site to investigate the effects of salt. I discovered this article: Why should I be careful about using salt on my driveway and sidewalks?

Then in my Twitter feed the other day, this article about how salt affects wildlife on the WWF (World Wildlife Fund site) appeared. Both are worth reading, because the effects of road salt on the environment are quite devastating.

I try to buy more eco-friendly de-icers, but I still feel dubious about sprinkling them up and down the driveway, up my walkway, and all over my front steps. I once ran out of salt and had a brainwave. I’d read somewhere that you could use kitty litter. I grabbed a cup without thinking—unfortunately it was the clumping kind, which I don’t EVER recommend using. It stuck together in huge, cement-like clumps and just made a big old mess. Not a good moment for me.

I found a great article on the Soil Advocates website that explores salt alternatives, like beet juice, cheese brine, and pickle juice. But until municipalities choose an alternative and stores readily stock them, I’m stuck with a salt-laced garden each spring.

Soil with too much salt buildup isn’t able to retain plant nutrients and it doesn’t hold as much water for plants, and some soil can become completely toxic to certain species of plants—hence the poor specimens that didn’t survive in my front garden (though the soil there in general is poor and I’ve been trying to amend it over time).

In researching salt-tolerant plants, I discovered that I have actually inadvertently planted quite a few of them in that garden (go me!). This kinda makes up for my kitty litter debacle, right? These are the plants that are doing quite well. For the lists below, I consulted several sources: a University of Vermont extension article, the Alberta Agriculture and Forestry ministry, a list from a professor of horticulture at Ohio State University who has done research on salt-tolerant plants, as well as a few growers’ websites that indicate salt-tolerance in the plants they sell.

Here are the salt-tolerant plants that I have in my garden

Sedum Autumn Joy (Autumn Stonecrop)
Moderate salt tolerance
I have this lovely, dependable fall bloomer, as well as a few other sedums that seem to like their sunny homes—even in the harsh soil conditions of my front garden. The bees love sedum flowers, and the plants are really easy to divide and transplant.
USDA zone 2-9

Butterfly weed (Asclepias tuberosa)
Moderate salt tolerance
I brought my Asclepias tuberosa home from a plant sale for the monarch butterflies who happen upon my garden. It took a couple of years for it to grow (apparently Butterfly Weed takes awhile to establish itself), but now the plant thrives in its potentially salty location. It’s a low grower, unlike its Common milkweed cousin, but it spreads outward and the vibrant orange blooms look really pretty next to my spurge. In 2017, it was the Perennial Plant Association’s Plant of the Year.
USDA zone 4-9

Blanket Flower (Gaillardia)
High salt tolerance
I really enjoy Blanket Flower blooms, even after the petals have fallen off! They look like something out of Dr. Seuss. Besides their affinity for salt, these plants love the sun, are drought tolerant, and the deer don’t seem to bother with them. Some varieties are more compact, low to the ground, and mounding, while others have blooms that reach 90 cm.
USDA zone 3-9

Russian sage (Perovskia atriplicifolia)
Moderate salt tolerance
I like to plant Russian sage in my raised beds because it is a bee magnet—and it just looks really pretty swaying in a summer breeze. But it also does well in that salty front garden. It basks in the heat and the sun, and can reach about 50 cm high. It’s a great complement to cut flowers, like vibrant yellow coreopsis.
USDA zone 4-9

Columbine (Aquilegia)
Moderate to high salt tolerance
I think I’ve only planted one variety of columbine in my front garden, maybe two, but a few renegade seeds from my neighbour’s garden must have blown in because I seem to have accumulated more. There are so many varieties and they all have different colour combinations. I think they’re pretty hardy in general because I saw a couple of plants growing through a crack in the concrete beside a café in my town. I wanted to rescue them!
USDA zone 3-9

A few more salt-tolerant plants

‘Karl Foerster’ reed grass (Calmagrostis acutifolia ‘Karl Foerster’)
High tolerance
There are a few ornamental grasses that are on the salt-tolerant lists I looked at, but this one appeared the most. Other picks include Blue lyme grass (Leymus arenarius), Chinese Fountain grass (Pennisetum alopecuroides), and ‘Elijah Blue’ fescue (Festuca glauca ‘Elijah Blue’). But back to ‘Karl Foerster’. I love the feathery plumes of this grass that enjoys both full sun or partial shade. This would make a nice backdrop to shorter salt-tolerant beauties.
USDA zone 4-9

Silver mound Artemisia (Artemisia schmidtiana Silver Mound)
Moderate salt tolerance
The foliage of this soft, feathery perennial looks like it might be delicate, but it can withstand a bit of salination. The cool, silvery-green hue of the foliage is a great accent to other cool colours, like blues and violets. Plant it in full sun or partial shade.
USDA zone 4-8

More plant picks…

• Bellflower
• Catmint
• Creeping Thyme
• Dianthus
• Daylilies
• Lady’s Mantle
• Sea Thrift
• Yarrow