Can You Mix Epsom Salt With Fertilizer – Is it good?

Gardeners have been using Epsom salt to enrich their plants.

Magnesium and sulfur present in Epsom salt help to make the plant bushier, produce blossoms, and make the plant leaves green.

But, can you mix Epsom salt with fertilizer?

Yes, gardeners who used Epsom salt with liquid fertilizer to enrich their ornamental plants say their plants grew larger when compared to other plants that are treated only commercial fertilizer.

Also, few gardening experts don’t recommend Epsom salt usage in garden. Check out this site to burst myths surrounding this mineral.

(At bottom of this article I gave my stance of this.)

Before dwelling further let me highlight few important benefits of using Epsom salt for plants.

Why Epsom Salt is Good for Plants?

Magnesium sulfate is a chemical name of Epsom salt. It is natural mineral that consists of magnesium, sulphur and oxygen.

This home available is prominently used in gardening to fertilize vegetable plants like tomato.

Let me put its benefits for plants in points.

  1. Chlorophyll, which is responsible for plant’s green color will be increased after magnesium rich fertilizer like Epsom salt. This mineral (magnesium) encourages plant to bloom and produce fruits.
  2. Improves plant’s ability to intake nutrients like nitrogen and phosphorus.
  3. Sulfur in Epsom salt helps to produce enzymes, vitamins and chlorophyll, which are essential for plant’s growth.
  4. Adding Epsom salt to the soil can avoid pests like beetles.

Magnesium and sulfur in Epsom salt contribute in chlorophyll production and formation of roots.

When transplanting seedlings outdoors, adding Epsom salt will save from transplant shock.

Can You Mix Epsom Salt with Fertilizer?

Yes, you can add Epsom salt with liquid fertilizer.

Magnesium and sulfur are two important nutrients for plant growth. Low levels of these minerals can turn leaves yellow.

In most cases, these two essential nutrients can be found in the soil. But, when you repeatedly grow plants in the same garden, nutrients in the soil depletes.

Adding Epsom salt is one of the effective ways to improve nutrient in the growing soil.

There are different ways with which you can add Epsom salt.

Some gardeners just sprinkle magnesium sulfate around the plant or add to the plant hole.

This will increase flowering ability of the plant as mentioned above.

Apart from directly benefitting the plant, Epsom salt increase nitrogen and phosphorus absorption ability of your plant.

These nutrients eventually make the plant bushier with dark green foliage.

How to Use Epsom Salt with Fertilizer?

You can use Epsom salt and fertilizer mixture on houseplants, ornamental plants like roses, shrubs, trees, lawns and vegetable plants.

Before mixing or using Epsom salt, test your soil to determine magnesium and sulphur deficiency.

Plants like beans and green vegetables can grow in low-magnesium soil. But, roses, tomatoes and pepper plants need high levels of magnesium and sulfate., states that adding Epsom salt to with fertilizer will act as supplement for regular plant fertilizer.

Add 2 tablespoons of Epsom salt to 1 gallon of water. Use this liquid fertilizer to spray on houseplants, flowering plants or vegetable plants.

Remember this: Epsom salt solution can’t substitute your fertilizer.

Mix Epsom salt + Baking Soda + Household ammonia + Water

You can make liquid fertilizer with above listed ingredients. (Source)

  • Water – 1 gallon
  • Epsom salt – 1tablespoon
  • Baking soda – 1 teaspoon
  • Household ammonia – ½ teaspoon

After mixing all ingredients, take ¼ cup of concentrated solution and mix it with 4 cups of water. Use this homemade liquid fertilizer once in a month.

Can you mix Epsom salt with miracle grow?

Like any other fertilizer, you can mix Epsom salt with miracle grow fertilizer. But, before mixing you must test your soil.

If your soil has abundant of magnesium, adding Epsom salt may harm the plant due to excess nutrients.

Similarly, before mixing Epsom salt with miracle grow, you must conduct soil test to determine magnesium deficiency.

Just visual inspection of plant leaves can’t tell deficiency of magnesium. As, magnesium intake improves plant’s ability to absorbs other nutrients, sometimes low levels of magnesium can manifest as other nutritional deficiency.

What plants don’t like Epsom salt?

University of Washington, states that you can use Epsom salt as a plant fertilizer. But, not all plants can tolerate high levels of nutrients.

For instance, ornamental plants are sensitive towards higher levels of minerals and eventually they might die.

As magnesium and sulfur are among secondary nutrients, every plant needs these elements. As the soil does have required amount of these nutrients, you don’t have to add Epsom salt.

In case, you add Epsom salt to such plants that can’t tolerate over fertilization, they might eventually experience stunt growth and die.

  • Carnivorous plants are adapted to grow in low mineral and depleted soil, applying Epsom salt even once can turn as a death trap for these insect-eating plants.
  • Woody plants are sensitive towards magnesium chloride. Epsom salt has similar elements in it. It’s better to avoid spraying Epsom salt on such small trees.
  • Apart from this, tropical plants, houseplants like Monstera, philodendron and alocasia are also sensitive towards Epsom salt. (Source)

What Plants like Epsom salt?

Fortunately, there are plant that developed tolerance towards higher concentration of magnesium. You can add Epsom salt along with liquid fertilizer without any adverse effect.

  • Tomato and pepper plants are heavy feeders; they require higher concentration of nutrients to produce fruits. You can add Epsom salt will certainly have positive impact on these veggies.
  • Other vegetable plants like cabbage, beans and corn thrive when you add Epsom salt once in a month.

How much Epsom salt to use for plants?

Before mixing Epsom salt with fertilizers, you must soil test. This will allow determining nutritional requirement of the growing medium.

Add 2 tablespoons of Epsom salt with 1 gallon of water.

There are different ways by which you can include this natural mineral with your fertilizer.

  • Top dressing, soil incorporation, soil drench or as foliar spray. In all these cases minerals in Epsom salt will benefit your plant.
  • If you’re not mixing with any fertilizer, then dig 1-2 holes beside plant and add ½ tbsp of Epsom salt to it. Whenever, you water the plant roots absorb required nutrients from the soil.

How to use Epsom Salt for Houseplants?

Unless your potting soil is completed depleted, your houseplants don’t need supplement fertilizers like Epsom salt.

Test your soil; if you notice deficiency in magnesium and sulfur, then you can add Epsom salt to houseplants.

Mix 1 tablespoon of Epsom salt with 1 gallon of water and use it to water your plant. Once in a month, it can acts as a substitute solution for water.

Side effects & Myths around Epsom salt Use on plants

If you apply magnesium in above mentioned dosage, then it will not harm your plants.

But, higher concentration of anything can actually kill your plants.

On other side, there are experts who don’t recommend using Epsom salt on plants.

  • Adding Epsom salt can’t avoid blossom end rot. This gardening problem is often caused due to low levels of calcium, so adding higher levels of magnesium (Epsom salt) will reduce plant’s ability to absorb calcium and further escalate the problem.
  • Using Epsom salt solution as leaf spray can result in leaf scorch.
  • There is no scientific evidence to back that adding Epsom salt to veggies like tomatoes and peppers has positive impact on its yield.


Gardeners are divided in two groups on the usage of Epsom salt in garden.

Some experts say that you can use it after mixing it with water and liquid fertilizer.

But, there are few gardeners who claim that there is no such positive benefit of using this mineral.

It might be confusing, so should you mix Epsom salt with fertilizer for plants?

I recommend using OMRI certified organic magnesium sulfate to enrich your growing soil that has low levels of magnesium. Yes, you can add this organic mineral to your fertilizer.

But, ensure to soil test before adding this liquid solution to plants.