Yep, just dissolve it in pure water and spray it on, your plants will all love you for it. Most plants here in Florida like some extra magnesium, because our heavy rains leach it out of the soil.
We got a good, heavy rain yesterday, early in the morning. My orchids are all out today and tomorrow but coming into the house again tomorrow night after a good spray with Epsom salts solution and mild fertilizer this morning. I'll spray the Vandas down with the hose again tomorrow before I bring them in, just because it's so much easier to do that outside than in.
