Which set of symptoms best indicates nitrogen deficiency in leafy ornamentals?

• A. Yellowing of older leaves, stunted growth, overall pale yellow foliage
• B. Yellowing of new growth only, increased growth
• C. Browning leaf margins with tips, curling leaves
• D. Dark green color with extra vigor

Answer: (A)

When a plant is short on nitrogen, it pulls this nutrient from older leaves to support new growth, so the first signs show up on the oldest foliage. Those leaves turn pale yellow as chlorophyll breaks down, and the plant’s overall growth slows, leading to stunted growth and a generally lighter, yellow-tinted appearance. This combination—yellowing on older leaves, slowed growth, and pale overall foliage—best indicates a nitrogen deficiency in leafy ornamentals.

Other patterns don’t fit because yellowing on new growth usually points to different issues (like iron deficiency or a micronutrient imbalance), browning margins with tips suggests water or salt stress, and a dark, vigorous green color implies sufficient or excessive nitrogen rather than a deficiency.