Is Epsom Salt Good for Houseplants?


On a daily basis, miraculous cures, particularly home-based ones that make use of common, affordable ingredients that can be found about the house, spread like wildfire throughout the Internet. The application of Epsom salt on houseplants and garden plants is a time-tested gardening technique that is often passed down from generation to generation. While some gardeners absolutely swear by it, others point out that there are no scientific studies to back up the claims.


Epsom salts are hydrated magnesium sulphate, and many gardeners think that using them would help their plants become greener and healthier. However, there is no evidence in the scientific community to support this claim. When your soil is lacking in magnesium, you have the best chance of seeing positive results from this practise.

Epsom Salt Outside the Bathtub

You have experienced the power of Epsom salt if you have ever submerged yourself in a hot tub that has been generously seasoned with various types of bath salts. It helps relieve aching muscles, softens the water in the bathtub, and allows you to relax and unwind after a hectic day. Epsom salt is made up of magnesium and sulphur, despite the fact that it seems to be a chunky, gritty kind of salt. In the year 1618, a farmer in Epsom, England made the observation that his cows did not like drinking from a spring that was nearby. After trying it, he came to the conclusion that the water with the strong flavour might be put to greater use, and as a result, Epsom became recognised as a spa town quite rapidly.

The question is, what does this substance that soothes the skin and reduces tension have to do with gardening? Everything, according to gardeners who have come before us. Providing increasing amounts of magnesium and sulphur is not a reasonable approach to the maintenance of houseplants, particularly in the absence of any indicators of insufficiency, according to Dr. Linda Chalker-Scott, an Associate Professor and Extension Urban Horticulturist at Washington State University.

The Magnesium Issue

Toss it into every planting hole, dissolve it in your watering water, spray a mixture of Epsom salt and water onto your houseplants’ leaves — Users of epsom salt report that it may result in plants that are both greener and healthier, according to the Washington State University Extension. However, you will have a difficult time locating scientific research that back up these assertions.

Both magnesium and sulphur are essential elements for the development and well-being of plants. The majority of soils, including those used for container gardening, have sufficient quantities of these minerals. Magnesium deficiency may occur in soils that have seen significant leaching or erosion, and prolonged leaching of potting soils can result in magnesium loss. It is possible to test the soil in a garden, but this is not an option for indoor plants. Soil testing is the only method that can be relied upon to identify mineral shortages.

Epsom Salt for Indoor Plants Research

An investigation on the effects of utilising an Epsom salt foliar spray was carried out by the National Gardening Association and was based on the findings that were reported by amateur gardeners working in their backyards. The findings led the researchers to the conclusion that spraying plants with a solution containing Epsom salt throughout the growth season resulted in greener foliage, bushier plants, and an increased number of blooms.

On the other hand, Dr. Linda Chalker-Scott, who has a PhD and works as an associate professor and extension urban horticulture, is not convinced. She observes that the effectiveness of Epsom salt in all of the research that she has studied depends on two factors: a lack of magnesium in the soil and crops that were cultivated in an intense manner. In such case, according to Chalker-Scott, it can be counterproductive rather than helpful.

Test it Yourself

The absence of significant evidence for the use of Epsom salt for houseplants that is supported by research doesn’t seem to bother the thousands of people who toss in a pinch of Epsom salt every time they repot a plant, or add Epsom salt to their watering mixture once a month, or spray the mixture on their plants’ leaves. Instead, they seem to be unfazed by the practise. According to advice given by, if you want to test it out for yourself and see whether it helps, you should use one tablespoon of Epsom salt.