Epsom salts are a naturally occurring chemical compound presented in the form of solid white crystallines. Often known for their pain and inflammation remedies, Epsom salts are more than just a bath product. They are an excellent source of nutrients for plants, providing a healthy dose of magnesium and sulfur. Using Epsom salts can give an extra boost to roses, tomatoes, peppers, and other plants that benefit from additional magnesium. With just a few treatments, Epsom salts can transform struggling plants back to their former glory.  

    However, Epsom salts are not a necessary supplement for all plants. Unless your soil lacks magnesium or sulfur, Epsom salts are generally used to bolster specific plants rather than being spread all over the garden. Learn about the best ways to use Epsom salts for plants, how to apply it to unhealthy plants, and other useful tips, including signs of magnesium deficiency in plants and Epsom salt precautions and benefits.   


    Ways To Use Epsom Salts

    Here are some ways to use Epsom salts for your plants:

    • When planting vegetables or roses, mix 1 tablespoon of Epsom salts into the planting hole before setting the plant.
    • After planting, mix 1 tablespoon of Epsom salts per gallon of water. Apply this solution around the root zone.
    • Reapply the liquid solution when your vegetable plants start blooming and again when small veggies begin growing.

    While Epsom salts may help with germination, chlorophyll development, and nutrient absorption, it’s important not to overdo applications on plants that don’t show signs of deficiency. Too much Epsom salts can accumulate in the soil and cause damage.

    Additionally, over-spraying Epsom salt on leaves can cause leaf scorch, causing the browning of leaves, which can lead to wilting. It is important to understand the health of your plant prior to applying Epsom salt. 

    Today’s Homeowner Tips

    Before widespread Epsom salt applications, test your soil to see if magnesium or sulfur are lacking. During the growing season, watch for deficiency signs like yellowing leaves, poor flowering, or low yields. Tomatoes and peppers indicate magnesium deficiency with yellowing or curling leaves and smaller fruits.


    How Epsom Salts Help Plants

    Epsom salts get their name from the mineral springs at Epsom, England, where they were originally discovered. Their chemical name is magnesium sulfate.

    When used as a fertilizer, Epsom salts provide two nutrients vital for healthy plant growth:

    • Magnesium (Mg): Magnesium assists with seed germination, green coloring, and fruit production. Magnesium deficiency causes leaves to yellow or brown.
    • Sulfur (S): Sulfur aids in forming plant proteins and vitamins. It promotes root growth and seed production while enhancing chlorophyll and dark green foliage.

    Roses, tomatoes, and peppers are heavy feeders that benefit from extra magnesium. Cucumbers, beans, and squashes also appreciate supplemental magnesium.

    Lawns, including grass and trees, generally don’t require Epsom salts. Too much magnesium without proper balance of other nutrients can inhibit plant growth.


    How To Apply Epsom Salts in the Garden

    Use Epsom salts sparingly as a supplemental fertilizer for magnesium-loving plants. Based on our years of experience, it is crucial to avoid overusing Epsom salts, which can accumulate in soil and cause salt damage. Follow the tips in the dropdown tabs below for using Epsom salts:

    • Mix 1 tablespoon per hole when planting roses, tomatoes, peppers, and other heavy feeders.
    • Mix 1 tablespoon per gallon of water and apply around the root zone every 2-4 weeks.
    • Time the applications to periods of rapid growth, like just before blooming and fruiting.
    • Mix 1- 2 tablespoons per gallon of water and mist onto leaves. Foliar absorption allows rapid magnesium uptake through leaves.
    • For roses, tomatoes, and peppers, apply 1 tablespoon per plant per application.
    • For other vegetables and ornamentals, use 1 teaspoon to 1 tablespoon per plant.
    • Apply every 2 – 4 weeks during the growing season, from planting through harvest.
    • Mist diluted Epsom salts onto leaves anytime to correct deficiency.
    • Water the soil around the plants. Avoid contact between dry Epsom salts and leaves, which can burn.
    • Mist diluted solution onto leaves to correct deficiency.
    • Add Epsom salts to a watering can and apply around root zones.
    • Use a hose-end sprayer with Epsom salt solution for larger garden areas.

    Signs of Magnesium Deficiency

    Watch for these signs of magnesium deficiency before applying Epsom salts. Specific plants show telltale symptoms when they need more of this nutrient.

    • Yellowing leaves with green veins
    • Few blooms
    • Yellowing and curling leaves
    • Smaller fruits
    • Yellowish leaves with green veins
    • Leaf tip and margin browning
    • Poor flowering and fruit set
    • Stunted growth

    Epsom Salts Precautions

    While it can help provide a nutrient boost, Epsom salts do require some caution in use. Follow these guidelines to avoid potential damage.

    • Avoid overuse that allows salts to accumulate in soil. Start with light applications.
    • Do not apply to plants showing no deficiency symptoms. Excess magnesium can hinder calcium uptake.
    • Avoid use on plants known to be magnesium sensitive.
    • Application to dry leaves can burn foliage. Dilute salts first and spray gently onto leaves.
    • Salts may damage concrete and metal tools. Rinse these after exposure.

    So, Is Fertilizing With Epsom Salts Beneficial?

    Used appropriately, Epsom salts can provide useful magnesium and sulfur bursts for deficient plants. However, Epsom salts are just one piece of effective gardening. Before reaching for the salts, ensure your soil has adequate organic matter. Choose plants suited to your growing conditions, and use recommended best practices like mulching, weeding, and pest control.

    With smart techniques, you can minimize the need for Epsom salts later on. But for plants showing deficiency, the occasional use of Epsom salts can fill seasonal nutrient gaps and keep tomatoes, peppers, roses, and other plants performing their best.


    FAQs About Fertilizing Plants with Epsom Salts

    Can I use Epsom salts for my vegetable garden?

    Yes, Epsom salts can supply helpful magnesium and sulfur for tomatoes, peppers, cucumbers, and other vegetables. Use 1 tablespoon per plant, applied every 2 to 4 weeks.


    When should I apply Epsom salts to plants?

    Time applications to periods of rapid growth, like just before blooming and as fruit develops. Mist diluted Epsom salts onto leaves anytime to correct deficiency.


    Can too much Epsom salts burn plants?

    Yes, overusing Epsom salts can damage plants. Use sparingly and dilute before foliar feeding. Never apply concentrated salts directly to dry leaves.


    Do Epsom salts help plants grow faster?

    While supporting healthy growth, Epsom salts do not accelerate growth speed. Ensure proper light, water, and care for your plants to support growth.


    Should I use Epsom salts on my lawn?

    Lawns rarely need Epsom salts. Test soil before widespread application to determine if magnesium is deficient. Even then, use Epsom salts very sparingly on lawns.


    Can you mix Epsom salts with fertilizer or compost?

    From our experience, we don’t recommend adding Epsom salts into fertilizers or compost for general use. It can upset nutrient balance. Use Epsom salts as supplemental feed for individual deficient plants.


    Are Epsom salts all-natural?

    Yes, Epsom salts are allowed in organic gardening. They derive from mineral deposits and break down into natural magnesium and sulfur.


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    Lauren Greene

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    Lauren Greene is a passionate storyteller with over 4 years of experience writing and editing. She attributes her expertise from working at local magazines, newspapers, and corporate marketing and communications teams. She has worked on content with topics ranging from plant care, home decor, and home improvement. Lauren resides in Raleigh with her adorable Shih Tzu. You can catch Lauren attending to her plants, spending time with her puppy, enjoying the greenway, or lifting weights at the gym when she’s not writing or researching the latest home improvement topics.

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    Sabrina Lopez

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