What Epsom Salt Can Do For Your Tomatoes & Why You Probably Don't Need It!

Epsom salts are one of those things that appear in gardening "hacks" all the time as a sort of fix-all. I try and avoid those clickbait articles and offer genuine advice. And while Epsom salts may be prevalent in hacks, they can genuinely offer a lot for your tomato plants, so let's have a look at what they can actually do.

Fix Yellowing Leaves

If your tomato plant is suffering from yellowing leaves where the veins stay green, then this is often a magnesium deficiency.

Many things can cause yellow leaves in tomatoes that are a lot worse than magnesium deficiency. But if your plant looks healthy and, importantly, the veins have stayed green, this could be your issue.

Luckily with the use of Epsom salts, this is also a really easy fix.

To fix you just need to spray a diluted mix of Epsom salts onto the leaves. Either do this in the early morning or into the evening to prevent the sun from burning the leaves.

This is the best use for Epsom salts and is what they are great at. If you have this problem then definitely use Epsom salts!

Fix A Magnesium Deficiency

If you have a magnesium deficiency in your soil, then using Epsom salts will certainly fix this and therefore help your tomato plants out. If you don't have a deficiency, though, then adding Epsom salts will do nothing.

They are not a plant feed or multi-nutrient fertiliser, they are a one-trick pony. Very useful if you are lacking in magnesium but not much else.

This is why they are not a fix-all for lots of different problems but rather a very effective fix for one particular problem.

With that said, magnesium deficiency can cause a range of problems, let's take a look.

Yellow Leaves

As we have already talked about, yellow leaves on your tomatoes - with green vines is a good sign that they are suffering from a magnesium deficiency.

A foliar spray is an easy way to fix this.

Poor Nutrient Uptake

A magnesium deficiency can inhibit the uptake of other important nutrients, which can lead to an overall unhealthy plant, even if the plant has access to all the other required nutrients.

If your plants look a little unhealthy or just aren't growing like you would expect then a little application of Epsom salts could go a long way.

Poor Growth

A lack of magnesium can actually prevent the plant from being able to photosynthesize properly. With this being the main way your plant grows then it will show up as a stunted, small, plant.

If you notice this early enough and fix with Epsom salts, then the plant will bounce back. if it goes on too long though, then the plant will never reach full size.

How To Apply?

For yellow leaves, you want to dilute your Epsom salts at a ratio of 10:1 with water. 10 parts water for 1 part Epsom salts.

You then spray this directly onto the leaves. Avoid doing it in the middle of the day as the sun may burn it onto the leaves.

In The Planting Hole

As a general soil improver, many people add Epsom salts to their tomato planting hole.

Diluted in Watering Can

You can also dilute Epsom salts into your watering can and water the soil around your plant.

YOU ONLY NEED TO DO THIS IF YOU HAVE A MAGNESIUM DEFICIENCY!

Adding lots of magnesium to your soil if you don't have a deficiency can actually be a problem all of its own. This is because your plant can struggle to take up other nutrients if there is an abundance of one.

This is particularly true with calcium, and a lack of calcium causes blossom end rot. The funny thing is that people recommend Epsom salts as a cure to blossom-end rot when it can actually cause it!