How to Mix Epsom Salts as a Fertilizer

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Known by scientists as magnesium sulfate, Epsom salts offer a simple and affordable way to amend garden soil. The salt contains magnesium and sulfur, both of which are crucial to plant growth. Sulfur is rarely lacking thanks to fertilizer use and acid rain, but magnesium deficiencies are common. Epsom salts add these elements to the soil and improve plant health. Readily available at drugstores, gardeners mix Epsom salts with water and then use it as a soil drench or foliar spray. How Epsom salts are mixed and applied depends on your specific need, and the results you get may vary.


How to Mix Epsom Salts as a Fertilizer
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Correcting Magnesium Deficiencies

Magnesium is often lacking in soils, especially in very light and sandy areas. The deficiency also occurs as a result of heavy rainfall or irrigation, both of which can leach magnesium from the ground. Adding magnesium to the soil with Epsom salts has proved effective and beneficial.


In order to correct a magnesium deficiency, you must first recognize it. Magnesium-deficient plants develop leaves that are yellow in the areas between the veins, a condition known as interveinal chlorosis. Suffering pants may also exhibit stunted growth and curling leaves. You can correct such a deficiency with Epsom salts. To do so, mix 1/2 to 1 ounce of Epsom salts with 3 gallons of water and apply it to the soil.

Epsom Salts for Boosting Roses

Epsom salts are often used to boost the growth of roses. Proponents claim the chemical produces greener leaves and more blooms. To boost your blossoms, mix 1/2 cup of Epsom salts into enough water to completely dissolve them and use the mixture to water the roses early in the spring. For ongoing fertilization, spray a mixture of 1 tablespoon of Epsom salts and 1 gallon of water onto your roses once every two weeks during the growing season. Avoid spraying on sunny days, however, or the plants may burn.


Epsom Salts for Other Plants

Epsom salts may also boost the growth of roses, peppers, tomatoes, lawns and other plants. Combine 1 tablespoon of Epsom salts with a gallon of water and spray your plants with it when they are first transplanted, when they first flower and when they set fruit. For larger plants, apply one tablespoon of Epsom salt for every foot of plant height.

You can also apply Epsom salts to lawns to help them grow greener. Dissolve 1 tablespoon of the crystals per gallon of water and apply it to your lawn, using enough of the mixture to wet the entire lawn. Follow up with a thorough soaking of just water to ensure the salts sink into the soil. You can also use a spreader, applying about 3 pounds of Epsom salts per 1,250-square-foot area.



Cindy Quarters

A recipient of a business and technology degree from the master's program at West Coast University, Cindy Quarters has been writing professionally since 1984. Past experience as a veterinary technician and plenty of time gardening round out her interests. Quarters has had work featured in Radiance Magazine and the AKC Gazette.