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  • Naomi Stephens | Permaculture Designer

Epsom Salts on Plants: How to Use, Pest Control, Cure Yellowing Leaves, Magnesium Deficiency

Updated: Mar 6

You may have heard about using Epsom salts on plants if you are a plant lover. Epsom salt is made of magnesium and sulfur, two essential minerals for plant growth.

Epsom salt is a naturally occurring mineral compound. It has a long history of use in gardening and agriculture, dating back to the early 1600s. Epsom salt can be beneficial for plants in several ways.

This blog post will discuss the benefits of using Epsom salts on plants and how to do it properly. We will also discuss the potential risks of using Epsom salts and how to avoid them.

In this post:

Epsom Salts provide essential nutrients.

Epsom salts provide essential nutrients for plant growth, including magnesium and sulfur. Epsom salt is a magnesium sulfate compound with a long history of use in gardening. Magnesium is an essential nutrient for plants, helping them to create chlorophyll and produce strong cell walls. Sulfates are also necessary for plant growth, as they help to improve soil structure and promote root development.

Epsom Salts improve drainage and aeration.

Epsom salts are a popular gardening product that can improve the drainage and aeration of compacted soils. The salts are rich in magnesium sulfate, which helps to break up clay particles and improve water infiltration. In addition, magnesium sulfate helps to promote root growth and encourages the uptake of other essential nutrients. Roots receive the oxygen they need to stay healthy, and this prevents waterlogging, which can lead to root rot. As a result, plants grown in soil amended with Epsom salts often have better drainage and aeration, leading to healthier growth.

Epsom Salts deter pests and diseases.

Gardeners have begun harnessing the power of Epsom salts to deter pests and diseases. When applied to the soil, Epsom salts help to correct nutrient imbalances and encourage robust and healthy plant growth. In addition, the magnesium in Epsom salts can help to prevent powdery mildew and other fungal diseases.

When sprayed on the leaves of plants, Epsom salts act as a physical barrier against aphids, whiteflies, and other troublesome pests. And because Epsom salts are non-toxic, they can be used safely around children and pets. Unlike Neem oil, a popular organic fertilizer, Epsom salt is not toxic to bees. You do not need to time your spraying to the mornings or evenings to avoid harming bees or other beneficial insects.

National Garden Association Study Proves Epsom Salts Benefits

The benefit of using Epsom Salts as a fertilizer ranks higher than using commercial fertilizers alone, and this has been proven thanks to tests run by the National Gardening Association, which found that roses treated with Epsom salts were giant, bushier, and more robust. They also found that peppers grown with Epsom salt grew bigger.

How is Epsom salt necessary for plants to make chlorophyll?

Chlorophyll is a green pigment that is found in the leaves of plants. It is essential for the process of photosynthesis, which helps plants to convert sunlight into energy.

Epsom salt is a source of magnesium, which is necessary for the synthesis of chlorophyll. Magnesium is involved in many important biochemical reactions in plants, including the production of ATP (adenosine triphosphate), the molecule that stores energy in cells.

Without magnesium, plants would be unable to produce chlorophyll and would not be able to perform photosynthesis. In addition, magnesium helps to strengthen plant cell walls, which can help to prevent disease and looting by pests. For these reasons, Epsom salt is essential for healthy plant growth.

How using Epsom Salts encourages seed germination.

Epsom salts are a natural magnesium source, essential for plant growth. Magnesium helps plants produce chlorophyll and activates enzymes necessary for seed germination. In addition, Epsom salts can help to loosen compacted soil, making it easier for roots to spread. For best results, mix one teaspoon of Epsom salt with one gallon of water and apply the solution to the soil around your plants. This simple step can encourage faster seed germination and help your plants to thrive.

What plants can you put Epsom salt on?

Many gardeners swear by the benefits of Epsom salt, and several plants can benefit from its use, for example:

  • - roses

  • - peppers

  • - tomatoes

  • - potatoes

  • - eggplants

  • - cabbage

  • - squash

  • - beans

Can too much Epsom salt hurt plants?

Epsom salt is made of magnesium sulfate, which can help plants grow more robust and resiliently. However, like anything else, too much Epsom salt can be harmful.

When applied in excess, Epsom salt can damage plant leaves, causing them to yellow and wilt. In extreme cases, it can even kill plants. So, how much Epsom salt should you use?

As a general rule of thumb, one tablespoon of Epsom salt per gallon of water is all needed. Dissolve the salt in water before applying it to your plants, and always follow the manufacturer's instructions. With some care, you can safely use Epsom salt to boost your plants - don't overdo it!

What does Epsom salt do for potted plants?

One of the main problems with potted plants is drainage. Epsom Salts will help prevent this by adding essential minerals to the soil and loosening it so water can drain more easily.

Epsom salt is a type of mineral that can benefit potted plants. It provides nutrients that plants need, including magnesium and sulfate. These minerals can help to encourage healthy growth and improve the appearance of foliage.

How to test your soil for a magnesium or sulfur deficiency

If your plants look sickly, it may be a sign that they lack magnesium or sulfur. The best way to test your soil is to take a sample to your local nursery or cooperative extension office.

You could also use a soil testing kit to determine the levels of magnesium or sulfur in your plant.

How to prevent magnesium deficiency with Epsom Salt

The usual sign of magnesium deficiency in house plants is chlorosis. Chlorosis is a condition that results in the yellowing of leaves due to a magnesium deficiency. While chlorosis can be caused by several factors, such as high pH levels or poor drainage, it is most often caused by a lack of magnesium in the soil.

Magnesium is an essential element for photosynthesis; without it, plants cannot produce chlorophyll. As a result, their leaves turn yellow, as seen in the picture below.

To combat chlorosis, you can add Epsom salt as instructed below.

How to use Epsom Salts for pest control

Epsom salt is toxic to many common garden pests, such as slugs and snails, but it can be used as an effective (and inexpensive) way to keep them at bay. Wondering how to use Epsom Salts for pest control? It's pretty simple. All you need to do is mix:

- ½ teaspoon of salt

- ¼ teaspoon of dish soap

- One quart of water

Then, pour the mixture into a spray bottle and spritz it on any pests.

How to use Epsom Salts on plants

Epsom salt can be used in two ways: as a foliar spray or as a root drench.

Foliar spray

When using it as a foliar spray, dissolve one tablespoon of salt in 1 gallon of water and apply it to the plant leaves.

Root drench

For a root drench, mix 1 cup of Epsom salt in 1 gallon of water and pour it around the base of the plant.

Be sure to only use Epsom salt on plants struggling to grow, as too much magnesium can be harmful. With proper care, Epsom salt can help your plants to thrive.

Can I sprinkle Epsom salt in my garden?

Yes, you can sprinkle Epsom salt in your garden, but it's essential to water it well afterward.

This will help ensure that the salt doesn't damage your plants.

When should I put Epsom salt in my garden?

Epsom salt can be added to your garden anytime, but it's especially beneficial when planting new seeds or transplants.

How often should I use Epsom salt in my garden?

You can use Epsom salt as often as you like, but experts recommend using it every two weeks for best results.

What flowers can you put Epsom salt on?

Epsom salt can be used on any flower, but it's especially beneficial for roses. The National Gardening Association Study conducted on roses showed that adding Epsom salt to the soil around roses can lead to more blooms.


With this, if you are an avid grower of house plants, you should find using Epsom salts very beneficial.

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