The Role Of Epsom Salt In the Garden

by Halley -Author at MIGardener

Epsom Salt a.k.a. Magnesium Sulfate

 A nutrient that every gardener and their grandparent and their grandparents grandparent knew about. It was an old wives' tale that Epsom salt could cure anything, and so farmers would see a nutrient deficiency and began putting Epsom salt on it for that very reason. To their amazement, the plants grew, became green, fruited, and their gardens were saved thanks to this very old household item. It is cheap, effective, and found in pretty much any pharmacy or big box store. But what is it? And why does Epsom salt work so well? Is it organic? All of this and more will be discussed in detail. 

What Is Epsom Salt?

 Epsom salt is MgSO4, and for non-chemistry majors, that is Magnesium Sulfate. It is considered a "salt" because it is not an element but a combination of two or more elements forming a crystalline compound. Much like table salt is Sodium Chloride, it's chemical compound is NaCl. Epsom salt is 1 part magnesium and 1 part sulfur. Magnesium and sulfur are very beneficial to the garden for separate reasons. 

Is Epsom Salt Organic?

Epsom Salt indeed is organic. Discovered in the late 17th Century, Epsom salts were the primary mineral source found in mineral springs, which became highly sought after for their healing properties. Baths popped up wherever these hot mineral springs were found. Many churches build and centered their campuses around these healing waters as well. Although most are made using chemical reactions in a lab, YES, Epsom salt can indeed be found in nature, making it organic! 

Magnesium's Role In The Garden

Magnesium is beneficial to plants from the beginning of their life; it assists with seed germination. Magnesium is vital and works in conjunction with Calcium to strengthen the plant cell walls. (See post: Role of Calcium In the garden) Magnesium also plays a crucial role in photosynthesis by assisting with chlorophyll creation; it works in Partnership with Nitrogen to bring new growth (See post: Role Of Nitrogen In The Garden).

When the two nutrient works together, they help increase the leaf's surface area to absorb more sunlight. Chlorophyll is used by plants to convert sunlight into food. It is also a wonderful help in allowing the plant to soak up phosphorus and nitrogen, which serve as vital fertilizer components for the soil. Magnesium is believed to bring more flowers and fruit to your garden because it helps to bring more phosphorus into the plant (See post: Role Of Phosphorus In The Garden), increasing the bounty and beauty of your space.

Sulfur's Role In the Garden

epsom salt

Sulfate, a mineral form of sulfur found in nature, is an equally important nutrient for plant life. Sulfate is essential to the health and longevity of plants and aids in the production of chlorophyll. It joins with the soil to make key nutrients more effective for plants, including nitrogen, phosphorus, and potassium. Sulfate also helps to regulate the pH or acidity of a garden. A garden with a pH of around 5.5-6.0 will generally outperform one with a pH of 7 or higher. This is because plants when grown in a pH of 5.5-6.0, can absorb many more of the nutrients in the soil, and therefore can grow faster than the same plant growing in a higher pH Soil.

Signs Of Magnesium Deficiency

The first sign of a Magnesium deficiency is by looking at the edges of leaves. A plant deficient in Magnesium will have brittle and brown edges to the leaves. The plant's leaves might also be curling downward and be cracking a bit. If left, a magnesium deficiency will ultimately stop a plant's growth, and it will slowly die after that.

How To Add Epsom Salt To The Garden

Epsom salt can be added to the garden in the form of a granular side-dressing. This way, the plants receive a little bit whenever it rains or is watered, or you can feed them whenever you water. I choose to do the watering method, which is less wasteful, and there is not as much risk with it running away from my plants. Mix in 2 tablespoons of Epsom salt to 1 gallon of water to feed plants! I use this mixture 1 time every 2 weeks. My plants stay green, happy, and grow fast!

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