Magnesium sulfate is an inorganic salt that is commonly marketed as “Epsom salts”. These salts are soluble in water and very efficient when there is a magnesium deficiency, either by mixing it in the substrate or by foliar application.
Foliar application is a technique to supply nutrients by applying the substance directly to the leaves so that they absorb it. Not any fertilizer can be applied in this way, you must know what you do because you can burn the plant.
In gardening and agriculture, Epsom salts are used to correct magnesium or sulfur deficiencies. The advantage of these salts over other magnesium additives such as dolomite is their high solubility, which also opens up the possibility of foliar application.
It also has the advantage that it is almost neutral in terms of pH, so applying this magnesium sulfate solution in cases of deficiencies will hardly change the pH of your substrate.
Foliar Application of Epsom Salts
- First of all you should heat the water to further improve the solubility.
- Then you add 1 teaspoons for every 1 liter of water.
- Spray the leaves liberally with this solution, just enough to cover them completely (also underneath), but they don’t need to be dripped with water.
It is important not to wet the buds, the absorption will not be ideal and the extra humidity can attract fungi and ruin your crop.
Regardless of whether you grow indoors or outdoors, wait until the dark hours before spraying your plants. Low temperatures and darkness favor absorption. In addition, water droplets can generate a magnifying effect that will cause light or rays of the sun to burn the leaves.
Providing magnesium in this way will ensure a quick recovery of your marijuana plants.
[Note: If you are preparing the soil yourself, you can add 1 or 2 teaspoons of sulfate for every 4 liters of substrate.]