For potted plants, mix a couple of tablespoons of the salt into your watering can once or twice a month. You can also sprinkle it in your garden’s soil to help your seeds germinate better. Tomatoes and peppers benefit the most because they both tend to have a magnesium deficiency. Add a tablespoon or so in with the soil when first planting, and then sprinkle more into the soil once mature.
Using Epsom Salt as a Natural Fertilizer in the Garden