Troubleshooting
Sweet orange problems — and how to fix them
Sweet orange (Citrus sinensis) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Scale insects and mealybugs
Common on indoor and conservatory trees. Wipe off with a cotton swab dipped in rubbing alcohol; treat severe infestations with horticultural oil or insecticidal soap. Check new growth and leaf undersides regularly.
Nutrient deficiency (yellowing leaves)
Interveinal yellowing on young leaves indicates iron or manganese deficiency (often a pH problem); overall yellowing points to nitrogen shortfall. Apply a balanced citrus fertiliser with chelated trace elements and check soil pH is 5.5–6.5.
Fruit drop before ripening
Caused by drought stress, temperature fluctuations, insufficient light, or root disturbance. Maintain consistent watering, avoid moving fruiting trees, and ensure at least 6 hours of direct sun daily.
Prevent sweet orange problems before they start
Most sweet orange issues are care-mismatch, not bad luck. Dial in the basics:
Looking for sweet orange in general rather than its problems? Read the full sweet orange care guide — light, water, soil and feeding.
Sweet orange problems — FAQ
Why is my sweet orange scale insects and mealybugs?
Common on indoor and conservatory trees. Wipe off with a cotton swab dipped in rubbing alcohol; treat severe infestations with horticultural oil or insecticidal soap. Check new growth and leaf undersides regularly.
Why is my sweet orange nutrient deficiency (yellowing leaves)?
Interveinal yellowing on young leaves indicates iron or manganese deficiency (often a pH problem); overall yellowing points to nitrogen shortfall. Apply a balanced citrus fertiliser with chelated trace elements and check soil pH is 5.5–6.5.
Why is my sweet orange fruit drop before ripening?
Caused by drought stress, temperature fluctuations, insufficient light, or root disturbance. Maintain consistent watering, avoid moving fruiting trees, and ensure at least 6 hours of direct sun daily.