Epsom salt, named for a bitter saline spring at Epsom in Surrey, England, is not actually salt but a naturally occurring pure mineral compound of magnesium and sulfate. Magnesium is an essential plant nutrient. It has a wide range of key roles in many plant functions. One of the magnesium’s well-known roles is in the photosynthesis process, as it is a building block of the Chlorophyll, which makes leaves appear green. It can be helpful for various situations in the garden. Here are just a few of them:
Improve Seed Germination
Using Epsom salt to improve the soil before seeding will give your plants a boost right from the start. Magnesium aids in seed germination and helps to strengthen cell walls, leading to stronger seedlings of greater number. For best results, incorporate 1 cup of salt per 100 square feet of tilled soil or mix 1 – 2 tablespoons into the soil at the bottom of each planting hole.
Increase Nutrient Absorption
Many commercial fertilizers add magnesium to help plant roots take up vital nutrients (nitrogen, phosphorus, sulfur.) For those using all organic materials to feed their gardens, adding Epsom salt to soil will improve absorption naturally, eliminating the need for processed chemical fertilizers.
Counter Transplant Shock
Plants and seedlings often wilt when moved between pots, from indoors to out, or from greenhouse to ground. To avoid this, try feeding transplants with Epsom salts; simply sprinkle some in the hole, remembering to add a thin layer of soil so that the roots don’t instantly come into direct contact with the concentrated minerals.
Green Up Foliage
The leaves of plants that aren’t getting enough magnesium will often start yellowing. This is because magnesium is an essential component in the production of chlorophyll. Try sprinkling Epsom salt around your plants, about 1 tablespoon per 12 inches of height once a month will benefit almost any plant, whether you want to green up your vegetable garden, trees, shrubs, flowers or grass.
Prevent Leaf Curling
Leaf curling can be caused by magnesium-deficiency. You can add Epsom salt to the soil around the base of the sick plant, or, for faster absorption mix 2 tablespoons of Epsom salt in a gallon of water and spray directly on the leaves.
Unfortunately Epsom salt won’t dehydrate slugs and snails like table salt (sodium chloride), but, it can still be used to deter pests. Epsom salt crystals are sharp so when sprinkled around plants, they can scratch and irritate the bodies and feet of unwanted critters in much the same way as diatomaceous earth. (Keep in mind that Epsom salt dissolves easily, so a rain will likely dissolve it into the soil.)
Grow Sweeter Fruit
Producing fruiti is the most taxing process in the life cycle of a plant. Apply Epsom salt to fruit and nut trees, bushes, and vines using the same methods and quantities stated for greening up plants. Increased energy means more sugar, allowing your plants to produce higher yields of sweeter, more nutrient rich fruit.
Tomato vines have a higher fruit to plant size ratio than average, leaving them more susceptible to magnesium-deficiency. Because of this, tomatoes should be fed Epsom salt twice as often as other plants. Tomato vines are also prone to calcium-deficiency, however calcium will compete with magnesium for absorption. The best way to deal with this to feed calcium at the roots and magnesium straight to the foliage. Water tomato vines with 2 tablespoons of Epsom salt dissolved in a gallon of water, every 2 weeks.
Peppers are another popular garden plant with a high fruit to plant size ratio. They should also be fed magnesium every two weeks to achieve higher yields of larger fruits. But for hot peppers, over-watering can lead to milder fruit so feeding the soil may be preferable. Sprinkle 1 tablespoon of Epsom salt for every foot of height around the drip line of your pepper plants once per week.
It is almost impossible to use too much Epsom salt in your garden. Magnesium sulfate is pH neutral, so it won’t harm your soil. The crystals break down into water, magnesium, and sulfur – three components which are beneficial in some way to most plants. Epsom salt is safe, easy to apply, and works fast to correct a variety of problems and increase the overall health of your garden. As if that weren’t enough, Epsom salt is also inexpensive making it one of the most perfect tools for the health-conscious, responsible gardener.