What is a common sign of phosphorus deficiency in leaves?

• A. Yellowing across the entire leaf
• B. Premature leaf drop
• C. Brown spotting along leaf margins
• D. Stunted growth with dark green color and purpling of stems or leaf tissues, especially in acidic soils

Answer: (D)

Phosphorus deficiency in leaves typically shows up as slowed, stunted growth along with a dark green color and a purplish tint on stems or leaf tissues, especially in acidic soils. Phosphorus is crucial for energy transfer and root and flower development, so when plants can’t access enough it slows their growth and tissue may accumulate pigments like anthocyanins, giving that purple coloration. The combination of limited growth and purpling is a telltale sign of low phosphorus, distinguishing it from other nutrient deficiencies. For example, yellowing across the whole leaf is more often linked to nitrogen or iron issues, brown spotty margins usually point toward potassium-related stress, and premature leaf drop can result from various stresses or deficiencies.