Flush salt de-icer from your trees

Salt used as a de-icer in winter is really hard on plants. Trees may show some scorching in their leaves or needles, and the tips will start to turn brown. When salt-laden snow piles up near a tree, salt seeps into the soil, drying out the tree’s roots. You might see bark discoloration, or canopy dieback. If left for too long, it can actually kill them.

Chris Fields-Johnson is a tech advisor for the Davey Tree Expert Company. He says trees can spring back if you flush the salt out of the soil with fresh, clean water as soon as you can.

"You’re going to flush the soil out, about an inch of irrigation water at a time, let it percolate down, and you’re going to repeat that multiple times. The rule of thumb is that it takes about 6” of water to flush out 50% of the excess salt in the soil," says Fields-Johnson. "So, it’s going to take repeated either rainfall events or irrigation to progressively flush the salt out of the soil."

The leaching can be done with a hose on slow trickle or by increasing your drip irrigation time. You could also build a basin around the tree to cover the entire root area. Slowly fill it with water, rinse, and repeat.

Fields-Johnson says for this to work, there has to be good soil drainage.

"If you put down a lot of water, even if it’s good fresh water onto a site, if it can’t drain anywhere, then the salt that’s dissolved inside of that fresh water can’t go anywhere either. So, as soon as that water evaporates off, the salt is still there," he says. "You’ve got to get that solution with the salt in it to move off the site either as run-off or better yet, as leaching water down to the groundwater table."