Troubleshooting
Seville Orange problems — and how to fix them
Seville Orange (Citrus × aurantium) 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.
Thorns
Mature Seville oranges are notably thorny, making pruning and harvest awkward. Wear gloves and long sleeves; thornier water-shoots can be removed to ease access without harming the tree.
Spider mites & scale
Common on indoor and conservatory citrus in dry air. Inspect leaf undersides and stems; raise humidity, wipe off scale, and treat with horticultural oil or insecticidal soap.
Chlorosis (yellow leaves)
Usually magnesium or iron deficiency or overwatering. Feed a trace-element citrus fertilizer and check drainage; persistent yellowing on new growth indicates iron.
Rootstock suckering
Because Seville orange is often used as rootstock, grafted citrus may throw vigorous, thorny suckers from below the graft union. Remove these promptly so they don't overtake the desired variety.
Prevent seville orange problems before they start
Most seville orange issues are care-mismatch, not bad luck. Dial in the basics:
Looking for seville orange in general rather than its problems? Read the full seville orange care guide — light, water, soil and feeding.
Seville Orange problems — FAQ
Why is my seville orange thorns?
Mature Seville oranges are notably thorny, making pruning and harvest awkward. Wear gloves and long sleeves; thornier water-shoots can be removed to ease access without harming the tree.
Why is my seville orange spider mites & scale?
Common on indoor and conservatory citrus in dry air. Inspect leaf undersides and stems; raise humidity, wipe off scale, and treat with horticultural oil or insecticidal soap.
Why is my seville orange chlorosis (yellow leaves)?
Usually magnesium or iron deficiency or overwatering. Feed a trace-element citrus fertilizer and check drainage; persistent yellowing on new growth indicates iron.
Why is my seville orange rootstock suckering?
Because Seville orange is often used as rootstock, grafted citrus may throw vigorous, thorny suckers from below the graft union. Remove these promptly so they don't overtake the desired variety.