I use Epsom salts on almost all my plants. I buy the cheapest I can find and without any fragrance ( my plants are very organic and prefer their natural perfume). Walmart has 2 lb. bags that are about $2.50-$3.50. They also have quart cartons occasionally for $.88 each. I sprinkle some in each hole for a new plant. I also sprinkle it around the bottom of all plants, in the ground and in pots. I use a lot in the spring and summer.
I also use the old brugmansia foliar feed that calls for Epsom salts. The salts need to be dissolved in warm water or they clog the sprayer. I spray nearly everything with that mix. I've never had any burn.
