Via Mag is critical in the formation of chlorophyll. It is also useful in aiding the absorption of phosphorus, which contributes to growth, flowering, and disease resistance. In addition, it helps plants absorb nitrogen and phosphorus. Adding Via Mag enhances color, promotes new flower and fruit, and improves root systems and stem strength. Safe to use and will not cause build up. For Soil: Add 2 Tbsp. per gallon of water if there are signs of magnesium deficiency or sprinkle 1 Tbsp. around the base of each plant and scratch into soil. For Hydroponics: apply 1 tsp. per gallon to your nutrient solution.