Epsom salts are essentially magnesium sulfate. This includes two of the nutrients that vegetables need: magnesium and sulfur. Of course you can find these two ingredients in many commercially made fertilizers, but they often come mixed along with other ingredients that you would not want to put near your food source. Epsom salts are an organic way to add much needed magnesium and sulfur to your gardening space. Before adding any additional nutrients to your soil, it is a good idea to test it first and see what it is actually lacking.
Magnesium helps produce fruit from the flowers. Making sure that your vegetable plants have enough magnesium ensures that your plants will be productive as far as fruit is concerned. Sulfur does two things for your vegetables: It promotes the growth of plant protein, which makes for a healthier plant, and enriches the nutritional value of the vegetables. Epsom salts also help to prevent blossom end rot. It is disheartening to see vegetables that are almost ripe, only to find that they are black and inedible where the blossom once was.
When planting your vegetables, you can sprinkle 1 tsp. of Epsom salts into the hole where you are planting your transplants. If you are planting seeds, it is best if you work the Epsom salts directly into the soil before planting. Sprinkle the salts in an even layer on top of your garden soil at the beginning of the gardening season. Till the soil as you normally would, mixing the salts in. You can also use a liquid mixture of the Epsom salts when the blossoms begin to appear on your vegetable plants. Mix 1 tbsp. of the salts into 1 qt. of water. Mix well and allow the salts to dissolve. Spray the salts on the blossoms.
Tomatoes and peppers are the two main vegetables that grow better when given an extra dose of magnesium sulfate. Peppers and tomatoes will both have increased production when using Epsom salts. It is important for you to keep picking the ripe vegetables to keep the plant producing more.