Diagnosing Citrus Nutrient Deficiencies Properly

Yellowing older leaves and dieback on orange trees suggest possible magnesium deficiency, but visual diagnosis is unreliable—symptoms of deficiency and toxicity often overlap. The only accurate method is leaf tissue analysis through your county Extension office.

Why Guessing Is Dangerous

Applying Epsom salts (magnesium sulfate) without confirmation can worsen imbalances. Excess magnesium interferes with calcium and potassium uptake.

Correct Process

1. Collect 20-30 mature leaves from non-fruiting terminals.
2. Submit to Extension lab (usually $20-30).
3. Follow the lab's specific fertilizer recommendations.

General Citrus Care

Use a complete citrus fertilizer with micronutrients. Water deeply but infrequently. Mulch. Monitor for pests.