Some folks use Epsom salts to feed plants that crave magnesium, such as rose bushes, with the belief that it will produce bigger flowers or basal breaks. If your soil is deficient of magnesium or sulfur, then Epsom salts will add these nutrients to the soil. But neither of these nutrients are deficient in most well-tended garden soils. The thing is, unless you do a soil test, you'll never know if your soil lacks magnesium and sulfur. If you are already adding any kind of organic material or organic mulch to the soil, it will likely have enough of both magnesium and sulfur already. Alternatively, if a soil test finds that you only need sulfur but not magnesium, then horticultural sulfur is a better product to use. Provided that your soil already has enough magnesium and sulfur, I don't think you can count on Epsom salts to make plants grow better.
