Epsom salts—the common name for the magnesium-sulfate compound (MgSO4). Epsom salt is a natural mineral that is made from hydrated magnesium sulfate. Epsom salts contain two micronutrients which are useful for the plant, and these are magnesium and sulfur. Hailed as ‘the best-kept gardening secret’ by some, though Epsom salts have been used in gardening for hundreds of years.
Many leafy vegetable crops, or some types of beans, will perform brilliantly even with very low magnesium levels; therefore, Epsom salts would not make any noticeable difference to the growth of these plants.
Magnesium-sulfate can increase cell uptake of key minerals, including nitrogen, phosphorus, and sulfur.
What it is used for
Primarily, roses, tomatoes, and peppers are the key plants that can take advantage of the magnesium contained in Epsom salts.
It's a general all purpose must haves for every gardener, either as an insecticide or as a natural plant enhancer.
How to Apply
Magnesium-sulfate is absorbed through the skin as well, so wear gloves when applying it to your plants.
You can apply a drench of one tablespoon of Epsom salts for every gallon of water to the soil after seeding.
To prevent root shock during transplanting, you can apply one to two teaspoons of dry salts directly to the hole before transplanting a bush or flowers. After tamping down the soil, water thoroughly.
For general pest control, mix one cup of Epsom salts with five gallons of water and spray onto foliage. For slug and snail control, sprinkle dry Epsom salts in the garden around the base of plants.
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