Master Gardeners: Epsom Salt uses for plants and in the garden

Published 12:32 am Saturday, June 27, 2020

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By Sheri Bethard

Texas Certified Master Gardener, Orange County Master Gardeners

Occasionally, you will see a post on social media or in a magazine that someone has used Epsom Salt on their plants. Well, after some research, this is what I have found on Epsom Salt and gardening.

First and foremost, before using Epsom Salt, you should test your soil to determine if it is low in magnesium. If you have been using Dolomitic Line, don’t use Epsom Salt as it also contains magnesium and you will have over-compensated for this nutrient and it could cause harm to your plant(s). Your soil could also be lacking in other nutrients that are needed more than the magnesium. It is a part of the chlorophyll molecule which is needed for photosynthesis and vital for plants to grow.

Epsom Salt can enhance your plants green color and also helps with flower blooming along with growing bushier plants. I have found sites saying this does work and others saying it does not work. So, I will leave that up to you to make your own decision. If you do decide to use Epsom Salt, here are some guides to use when mixing.

You can use Epsom Salt as a foliar spray for your plants leaves by mixing 2 Tablespoons of Epsom Salt to one gallon of water. For soil drenching, use ½ cup per gallon.

For Roses, especially, you can mix 1 Tablespoon per gallon of water for each foot of height of the shrub. Apply in spring and then again after blooming has ceased.

For Tomatoes and Peppers, apply 1 Tablespoon around each transplant when you set them out or spray 1 Tablespoon per gallon on your plants while transplanting then again after the first bloom and fruit set.

For your soil or lawns before planting, broadcast 1 cup per 100 square feet mixing well with the soil then plant your sod.

Now, don’t plan on using Epsom salt on a regular basis as this could cause to much salt build up in the soil. Epsom salts can rejuvenate tired plants and reduce stress or give them a kick in the pants. Personally, I would not use unless my soil test said I had a magnesium deficiency, but you may have had luck with it and go forward and grow.

Our Master Gardener Hot-Line is open Tuesday and Thursdays from 10 a.m. – 2 p.m., call 409 882-7010 with your questions. If after hours, please send your question to our Contact Page at or reach us on our Facebook page Orange County Texas Master Gardeners and you will receive an answer within 24 hours.