Boost plant health with Epsom salt

The idea

Prepare and apply Epsom salt (magnesium sulfate) to garden plants. Mix 1 tablespoon of Epsom salt per gallon of water. For a 2-gallon watering can, use 2 tablespoons of Epsom salt.

Apply the solution in two ways:

1. Foliar feeding: Spray the leaves of tomato, cucumber, and squash plants until they are thoroughly wet.
2. Root drenching: Pour the solution directly onto the soil around the base of the plants. For a large tomato plant, drench for about 3 seconds. For two cucumber plants and two squash plants, drench for about 10 seconds each.

This application should be done mid-season, around the time plants start bearing fruit or flowering, and generally only once or twice a season. Apply in the early morning to avoid heat stress and allow for better absorption.

Why it works

Epsom salt provides magnesium and sulfur, which are essential micronutrients for plants. Magnesium helps build chlorophyll, which is crucial for photosynthesis and gives plants their green color. Sulfur aids in the development of enzymes and proteins, vital for plant growth and function.

While macronutrients (nitrogen, phosphorus, potassium) are needed continuously, micronutrients like magnesium and sulfur are required in smaller amounts. Applying Epsom salt ensures these specific needs are met, leading to healthier, more productive plants. Foliar feeding allows for immediate absorption through the leaves, while root drenching provides nutrients to the root system.

Try it

1. Mix 1 tablespoon (about 15 ml) of Epsom salt per gallon (about 3.8 liters) of water in a watering can.
2. In the early morning, spray the leaves of your fruiting plants (like tomatoes, cucumbers, or squash) until they are thoroughly wet.
3. Immediately after foliar feeding, drench the soil around the base of each plant with the remaining solution. For a large plant, a 3-second pour is sufficient; for heavy feeders or multiple plants, adjust accordingly.
4. Repeat this process only once or twice per growing season, typically mid-season when plants are flowering or setting fruit.

Watch out for

• Do not overuse: Epsom salt provides micronutrients, and plants only need small amounts. Excessive use can harm plants.
• Timing of application: Apply in the early morning to allow leaves to absorb the solution before the sun gets too hot, preventing leaf scorch and ensuring better absorption.
• Mixing with other fertilizers: Epsom salt can be mixed with fish emulsion, which provides macronutrients (N-P-K) and other trace elements, for a comprehensive feeding. However, ensure any other fertilizers are compatible before mixing.