Rock salt (sodium chloride) can harm your plants and rob the
soil of nutrients. Ice-melt products made of potassium chloride, magnesium
chloride or calcium chloride are slightly less harmful; they are less corrosive
and they contain nutrients that plants can use.
Don’t bother
applying ice melt when temperatures are extremely cold. Rock salt will be
effective down to 15˚F. Calcium chloride will be effective down to 5˚F. There’s
no product that will work below 5˚F unless you apply it very, very heavily.
