Troubleshooting
Quince problems — and how to fix them
Quince (Cydonia oblonga) 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.
Quince leaf blight
Diplocarpon mespili causes dark blotches, yellowing and early leaf drop in wet summers. Rake up and destroy fallen leaves, prune for airflow, and avoid overhead watering.
Brown rot
Monilinia fungi rot fruit on the tree, leaving brown spreading patches with buff pustules. Remove and bin mummified fruit promptly and avoid bruising at harvest.
Fruit cracking and small fruit
Caused by erratic watering during fruit swell. Keep soil moisture even and mulch well; fruit also stays small on stressed or unfed trees.
Codling moth and fireblight
Codling moth grubs tunnel into fruit; pheromone traps help. Fireblight (Erwinia) can blacken shoot tips in a 'shepherd's crook' — prune well below affected wood and disinfect tools.
Prevent quince problems before they start
Most quince issues are care-mismatch, not bad luck. Dial in the basics:
Looking for quince in general rather than its problems? Read the full quince care guide — light, water, soil and feeding.
Quince problems — FAQ
Why is my quince quince leaf blight?
Diplocarpon mespili causes dark blotches, yellowing and early leaf drop in wet summers. Rake up and destroy fallen leaves, prune for airflow, and avoid overhead watering.
Why is my quince brown rot?
Monilinia fungi rot fruit on the tree, leaving brown spreading patches with buff pustules. Remove and bin mummified fruit promptly and avoid bruising at harvest.
Why is my quince fruit cracking and small fruit?
Caused by erratic watering during fruit swell. Keep soil moisture even and mulch well; fruit also stays small on stressed or unfed trees.
Why is my quince codling moth and fireblight?
Codling moth grubs tunnel into fruit; pheromone traps help. Fireblight (Erwinia) can blacken shoot tips in a 'shepherd's crook' — prune well below affected wood and disinfect tools.