Use plant booster products with high levels of Magnesium. Read labels well and apply the correct dose.
Use organic products to cure magnesium deficiency: dolomite lime, Epsom salts, worm castings, garden lime, or magnesium sulfate. We recommend using Epsom salt or Magnesium sulfate since these are water-soluble. Epsom salts are best for hydroponic systems.
To use Epsom salts use a ratio of a gallon of water: a teaspoon of Epsom salts.
Use Calcium- Magnesium product or Cal-Mag. This is a trusted Magnesium and Calcium corrector that is available in most cannabis growing supplies shop.
Correct root pH. Incorrect pH can lead to poor absorption of nutrients. Keeping the correct root and soil pH can help prevent the occurrence of any deficiency. Also, adding magnesium supplements to roots or soil with incorrect pH won’t do any good. The nutrient will simply stay in the soil and this can affect the absorption of other nutrients. Remember, when you’re growing in soil root pH should be from 6.0 to 7.0 and when you’re growing in hydro, root pH of 6.0 to 6.5 is needed for efficient Magnesium absorption.
Flush your system with clean, pH-balanced water. Flushing will help remove nutrient salts which may affect your plant’s ability to absorb Magnesium and other nutrients. Also, this can help improve pH and maintain pH correctly.
It can take a week for magnesium treatments to completely work. Expect that the affected plant parts will never recover but new growth will eventually appear to replace these old growths.