Is Epsom Salt Good for Hydrangeas?

Most gardening experts practice and recommend adding Epsom salt along with fertilizer to enrich their plants.

Gardeners prominently use Epsom salt to fertilize flowering plants like hydrangeas.

Also known as magnesium sulfate, Epsom salt can get rid of the yellowing of leaves, encourage blooming, and promote bushier plants.

Hydrangeas are popular ornamental plants with beautiful flowers that are commonly used in bouquets and for decoration in gardens. But when it comes to growing hydrangeas, plant owners often ask if Epsom Salt is Good for Hydrangeas.

Epsom salt is good for hydrangeas as it can help promote better flower production.

Adding a small amount of Epsom salt to the soil doesn’t harm your plant; however, it should not be considered a substitute for adequate soil preparation and plant maintenance.

Epsom salt has various uses, such as promoting plant growth. But some experts say it can only benefit a little.

Know your Plant – Hydrangeas

is epsom salt good for hydrangeas

Hydrangeas are beautiful flowering plants that are popular in gardens all around the world for their different colors of bloom. Hydrangeas are leafy bushes that belong to the Hydrangeaceae family. 

They are originally from Asia and the Americas and have been popular decorative plants for many years. One fascinating thing about hydrangeas is that the color of their flowers can change depending on the acidity of the soil.

When the soil is more acidic, hydrangea flowers tend to be blue. Whereas when the soil is more alkaline, the flowers tend to be pink. If the soil is neutral, the flowers may be white or green. This ability to change colors makes hydrangeas a fascinating and versatile plant to have in your garden.

Hydrangeas come in many different varieties, each with its unique features. Some hydrangea types, such as the mophead, have flower heads consisting of smaller flowers in a round shape.

Others, like the lace-cap hydrangea, have a flatter, more delicate flower head. There are even climbing hydrangeas that can grow up walls.

What Does Epsom Salt Do for Hydrangeas?

Epsom salt is a mineral compound composed of magnesium and sulfate. Some gardeners believe that adding Epsom salt to the soil can help hydrangeas produce bigger and brighter blooms. But what exactly does Epsom salt do for hydrangeas?

Well, magnesium is an essential nutrient for plants, and it helps with the production of chlorophyll. It is important to note that sulfur plays a crucial role in the production of plant proteins.

Both of these nutrients are vital for the growth and health of hydrangeas, which is why adding Epsom salt to the soil can be helpful.

In addition to providing essential nutrients, Epsom salt can also help to adjust the pH level of the soil. Hydrangeas prefer acidic soil, and adding Epsom salt can help to lower the pH level, making the soil more acidic. It results in bluer flowers, which is what many plant owners desire.

Is Epsom Salt Good for Hydrangeas?

Yes, it is good for hydrangeas and other plants as well.

Epsom Salt Promotes Bigger, and Brighter BloomsEpsom salt can help hydrangeas produce bigger and brighter blooms by providing them with essential nutrients.

Also, magnesium is a vital nutrient for plants, and it aids in the production of chlorophyll. Sulfur is necessary for plants to form proteins, promoting growth and development.

1. Adjusts Soil pH

Hydrangeas prefer acidic soil, and adding Epsom salt can help to lower the pH level, making the soil more acidic. It can result in bluer flowers.

However, note that the color change is not guaranteed and depends on various factors, including the original soil pH, the type of hydrangea, and the amount of Epsom salt used.

2. Improves Plant Health

Epsom salt can help improve the overall health of hydrangeas. Magnesium is known to help plants absorb other nutrients, such as nitrogen and phosphorus, more effectively.

Sulfur is essential for the development of strong roots, which can help hydrangeas withstand drought and other stresses.

3. Epsom Can Acts as a Fertilizer

Epsom salt can also work as a fertilizer for hydrangeas. The magnesium and sulfur in Epsom salt can help plants absorb other important nutrients, such as nitrogen and phosphorus, which makes the plant stronger, healthier plants with bigger and brighter blooms.

(Check this out: Do Hydrangeas Like Coffee Grounds?)

4. Strengthens Stems

Another benefit of using Epsom salt for hydrangeas is that it can strengthen the stems of your plants. Magnesium is an important nutrient for plant cell walls, and it can help hydrangeas grow stronger and more resilient stems.

How to Use Epsom Salt for Hydrangeas?

Here’s how to use Epsom salt for hydrangeas – 

Right Amount

Use the right amount of Epsom salt for your hydrangeas. Too much can cause nutrient imbalances, while too little may not have any effect.

Only use about one tablespoon of Epsom salt per gallon of water for outdoor plants or one teaspoon per four-inch pot for indoor plants. However, it’s best to follow specific instructions for your particular type of hydrangea and soil conditions.

Mix Epsom Salt with Water

Dissolve the Epsom salt in warm water before applying it to your hydrangeas. Adding water to the salt helps it dissolve easily and ensures even distribution.

Apply Epsom Salt Solution to the Soil

Apply the solution of dissolved Epsom salt to the soil around your hydrangeas. Avoid getting the solution on the leaves. Water the soil lightly after applying the Epsom salt solution to help it soak in.

Repeat it as Needed

You can repeat the application of Epsom salt solution as needed throughout the growing season. Check your plants for any signs of nutrient deficiencies or other problems.

Check this out: Do Hydrangeas Repel or Attract Mosquitoes?

How Much Epsom Salt Do You Put on Hydrangeas?

For outdoor hydrangeas, it is best to use one tablespoon of Epsom salt per gallon of water. For indoor plants in four-inch pots, use about one teaspoon of Epsom salt per pot. 

When to Apply Epsom Salt on Hydrangeas?

If you’re planning to use Epsom salt for your hydrangeas, you should know the right time to apply it.

The best time to use Epsom salt on plants is during the growing season, which is from late spring to early fall. 

At this time, your hydrangeas can receive the most benefit from added nutrients as they are actively growing.

It’s a good idea to apply Epsom salt to your hydrangeas right before a rain or watering session. By doing so, the salt will dissolve and spread uniformly across the soil. 

Is Epsom salt a good fertilizer for hydrangeas?

Many people suggest using Epsom salt as a natural fertilizer for hydrangeas. It contains magnesium and sulfur, two important nutrients that can help to promote healthy growth and vibrant blooms in your hydrangeas.

Magnesium helps to promote healthy foliage, while sulfur is important for the development of enzymes and proteins that are necessary for plant growth.

When applied properly, Epsom salt can help to improve the overall health and appearance of your hydrangeas. It can help to enhance the color and size of blooms, as well as strengthen the stems and prevent diseases.

Does Epsom salt promote hydrangeas flowering?

Yes, Epsom salt can help promote hydrangeas flowering. Epsom salt is a naturally-appearing mineral combination of magnesium and sulfate.

Magnesium is a key nutrient for plant growth and helps to promote strong roots, healthy leaves, and abundant blooms. So, Epsom salt really helps to promote blooming.

Does Epsom salt change the color of hydrangeas?

Epsom salt can’t help in changing the color of hydrangeas. The pH of the soil defines the color of hydrangea flowers.

Hydrangeas with blue flowers grow in acidic soil, while hydrangeas with pink flowers grow in alkaline soil. You can change the color of your hydrangea flowers by just modifying the pH of the soil. To make your hydrangeas blue, add aluminum sulfate to the soil. To make your hydrangeas pink, add lime to the soil.

(Read my article on How to grow hydrangeas in clay soil?)

What plants don’t like Epsom salt?

Not all plants like Epsom salt. Some plants that are sensitive to Epsom salt include –

  • Carnivorous plants – pitcher plants, sundews, and Venus flytraps don’t like Epsom salts.
  • Indoor tropical plants – tropical palm, alocasia, and fiddle leaf fig.
  • Woody Plants – Pine trees and coniferous don’t like Epsom salt at all.

If you are trying to decide whether or not your plant likes Epsom salt, it is best to be cautious and not use it. Epsom salt can be harmful to plants in large doses.

(Check this: Can You Mix Epsom Salt With Fertilizer?)

Hydrangeas Plant Care Tips

Hydrangeas are beautiful and popular plants that require proper care to thrive. Here are some plant care tips to help keep your hydrangeas healthy and vibrant –

Soil – Hydrangeas prefer well-draining soil that is rich in organic matter. Amend the soil with compost or other organic material to improve soil structure and provide nutrients.

Fertilizing – Hydrangeas benefit from regular fertilization with a balanced fertilizer that contains nitrogen, phosphorus, and potassium. Apply fertilizer in early spring and again in mid-summer for best results.

Pruning – Prune your hydrangeas in late winter or early spring to promote healthy growth and flowering. Remove any dead or damaged wood, and cut back the previous year’s growth to the first pair of healthy buds.

Watering – Hydrangeas need regular watering, especially during the summer months when the weather is very hot and dry. Water deeply and frequently to keep the soil evenly moist but not soggy.

Sunlight – Hydrangeas prefer partial shade or filtered sunlight, especially during the hottest part of the day. Too much direct sunlight can cause the leaves to wilt and the blooms to fade.

Mulching – Apply a layer of mulch around the base of your hydrangeas to help retain moisture and regulate soil temperature. Use natural mulch such as shredded leaves, straw, or bark chips.

Must read: How to Use Eggshells for Hydrangeas?


Hydrangeas are easy to care for plants, and using Epsom salt can definitely help them. By providing regular watering, well-draining soil rich in organic matter, and regular fertilization, your hydrangeas can thrive and produce abundant blooms. 

Moreover, pruning in late winter or early spring, providing partial shade, and applying a layer of mulch can also help promote healthy growth and flowering.

With proper care, your hydrangeas can be a source of beauty and enjoyment in your garden. And if you’re looking to boost their growth and flowering, consider using Epsom salt as a natural and effective supplement.