Magnesium Deficiency
When plants are deficient in magnesium, older leaves typically develop interveinal yellowing while the veins remain green, followed by possible leaf curling, necrotic spots, and premature leaf drop as symptoms worsen. Necrosis (browning) develops suddenly between the veins, usually within 24 hours. Magnesium deficiency is often confused with iron deficiency, which affects young leaves first, or potassium deficiency, which usually causes marginal yellowing and scorch on older leaves.
