Yellowing Leaves on a Young Thompson Pink Grapefruit Tree

Diagnosing the Cause

Yellowing leaves on citrus can signal nutrient deficiency, watering issues, or pests. Key clues:

• Older leaves yellow, newer leaves pale green: Nitrogen deficiency.
• Yellow leaves with green veins: Iron deficiency (chlorosis).
• Outer leaves yellow, branch dieback: Overwatering or poor drainage.
• Mottled yellowing with stippling: Spider mites (check leaf undersides).

Corrective Actions

1. Watering: Provide ~3.5 inches of water per week. Let soil dry between waterings; keep area under canopy free of mulch, grass, or weeds.
2. Fertilize: Use a slow-release citrus fertilizer with micronutrients (including iron). Avoid cheap, high-salt fertilizers.
3. Inspect for Pests: Check leaf undersides for mites, scale, or aphids. Treat with horticultural oil or insecticidal soap if found.

Adjust care based on the specific symptom pattern for a healthier, more productive tree.