Updated: Mar 2, 2020
Epsom salt, magnesium sulfate, is an inexpensive measure to improve your garden. Epsom salt helps germinate seeds, makes plants grow bushier and produce more flowers (by increasing chlorophyll production), and also deters pests. Magnesium allows plants to absorb valuable nutrients from the soil, like nitrogen and phosphorous, which are both very important to plant growth.
Tests done by the National Gardening Association confirms that roses fertilized by epsom salt grow bushier and produce more flowers. It also makes pepper plants grow larger than those only treated with commercial fertilizer.
When to use epsom salt?
Take visual cues from your plants to recognize if the soil is being depleted of certain nutrients. If all the plant's leaves turn yellow, that might be a sign the plant needs more sulfate. If flower leaves turn yellow between the veins (veins stay green), the plant may need more magnesium. Some nutrient disorders display the same way, so if you want to be certain you can test the soil.
Improve seed germination
Add epsom salt to the soil as an amendment before seeding. This mineral will aid in seed germination as well as strengthen the plant's cell walls which means stronger seedlings.
1 cup of epsom salt per 100 sq. feet of tilled soil
Mix 1-2 tablespoons into the soil at the bottom of each hole before dropping the seed in.
Counter transplant shock
Sprinkle epsom salt into the bottom of transplant holes or make an epsom transplant solution.