Its wide availability tempts many gardeners to use it.
But is Epsom salt good for plants, and should we use it in our gardens?
Here’s what the research reveals.
Credit:Martina Unbehauen / Getty Images
Linda Chalker-Scott is a horticulturist and an associate professor at Washington State University.
What is Epsom Salt?
Epsom salt is a naturally occurring mineral compound of magnesiumand sulfurknown as magnesium sulfate.
Credit: Cameron Sadeghpour
Sulfur builds proteins and in fruit, it is important to flavor.
Chemically, it is classed as a salt.
Yet Epsom salt remedies remain popular when planting crops.
Soil deficiencies of both these elements are rare in gardens, especially of sulfur.
Some sandy and acidic locations can lose magnesium in heavy rains.
Many conditions can cause yellowing leaves, so Epsom salts may not help and can be harmful.
Magnesium deficiency has a particular look: The leaf veins remain green while the surrounding tissue yellows.
If your spray is too strong, it can cause salt injury, burning the plant.
Blossom-end rot is the culprit behind icky dark soft blotches on the base of tomato fruits.
It usually occurs early in the season, triggered by insufficient calcium uptake.
However, Epsom salt doesnt contain calcium or improve its uptake.
Epsom Salt for Weeds
Epsom salts are sometimes recommended as a home remedyweed killer.
Test Your Soil
Before you add Epsom salt to your garden,test your soil.
Then follow the reports recommendations for amending soil at the proper tool rate for your space.
The best way to nurture healthy, nutrient-rich soil is withannual applications of compost.
Supplementing with a slow-release organic fertilizer is usually sufficient to keep fast-growing annual plants thriving.
Chalker-Scott L, Guggenheim R.Epsom Salt Use in Home Gardens and Landscapes.
Washington State University Extension.
