Ice Melt and Plant Health
Most people are aware that de-icing salt products can damage and corrode automobiles, but plants near sidewalks, driveways, and roads are also at risk for damage. Leaf discoloration, premature leaf drop, and even twig dieback can occur when a plant is exposed to too much salt.
Salts are applied before or after snow or icy rain. The salt dissolves in the water and creates a brine with a lower freezing point, keeping paved surfaces safe by preventing ice formation. When cars and people move through this water, it can splash onto the foliage or root zone of nearby plants. Plants do not have a way to shed excess salt, so it builds up in the plants tissues, affecting appearance and health. Salt accumulation can also occur when salt-heavy snow is shoveled or plowed into garden beds.
Late winter or spring salt applications are most likely to cause damage to deciduous plants. To protect plants that you think may be in danger of salt damage, flush the area around their roots with water to leech the salts, put up burlap barrier between the plant and the paved surface, or use an alternative to sodium chloride, like calcium chloride.
There are plants that are more tolerant of salt – including favorites like daylilies, ornamental grasses, rugosa roses, and junipers. If you notice a particular spot in your yard has problems with dieback each winter, consider researching plants that can withstand high salinity and cold winter temperatures, or avoid planting these areas entirely.
Prepared by Lindsey Smith, Collections Curator