Epsom Salt! How and Why to Add it to Your Indoor Garden (2024)

Let’s head into the weekend with another garden hack that you may have hanging around your house! It’s called magnesium sulfate or MgSO4 7H2O or magnesium sulfate heptahydrate or most commonly known as Epsom Salt 😊

It breaks down into essentially magnesium and sulfur (and oxygen) which are micronutrients plants need. We talked about the 2 of the 3 macros in the matchstick post (phosphorus and potassium) but plants also need micros to help them absorb their macros.

So what does Epsom salt do to your plants and how much should you use? Epsom salt is really great for flowering plants. For the Coco and Seed kits that includes Thai hot peppers, eggplants, and tomatoes. Will your plants grow without added Epsom salt, of course! There is no need to go out and get it if you don’t already have some readily available.

But if you do have some what this does is improve flower bloom, really makes your green leaves greener, increase flavor, increase nutrient absorption, and may increase yield due to the added benefits.

So how much do you use? This is a bit trickier to determine as it varies from different sources. Personally, with the hydroponic nutrients 1/4th teaspoon per gallon is recommended. Some places list up to two tablespoons per gallon!! That’s a big difference. I recommend starting with less and working your way up to 1 teaspoon, then from there if your plants are enjoying it and looks like they can use more then venture slowly. Too much, just like with anything, can be harmful.

This mixture can be used on regular houseplants, plants in soil, hydroponics and outdoor gardens and flowering or non flowering plants. It benefits flowering plants more but go wild!