Troubleshooting
Smyrna quince problems — and how to fix them
Smyrna quince (Cydonia oblonga 'Smyrna') 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)
Angular brown spots on leaves leading to early defoliation; more severe in wet seasons. Remove and destroy fallen leaves; apply copper-based fungicide at bud break in high-risk areas.
Fireblight (Erwinia amylovora)
Bacterial disease causing blossoms, shoots, and fruit to wilt and blacken as if scorched. Prune out affected wood well below infection; sterilise tools between cuts. Most problematic in warm, wet spring weather.
Brown rot (Monilinia fructigena)
Fruit rots on the tree, often with concentric rings of white spore pustules. Remove and dispose of all mummified fruit; ensure good air circulation through pruning.
Prevent smyrna quince problems before they start
Most smyrna quince issues are care-mismatch, not bad luck. Dial in the basics:
Smyrna quince problems — FAQ
Why is my smyrna quince quince leaf blight (diplocarpon mespili)?
Angular brown spots on leaves leading to early defoliation; more severe in wet seasons. Remove and destroy fallen leaves; apply copper-based fungicide at bud break in high-risk areas.
Why is my smyrna quince fireblight (erwinia amylovora)?
Bacterial disease causing blossoms, shoots, and fruit to wilt and blacken as if scorched. Prune out affected wood well below infection; sterilise tools between cuts. Most problematic in warm, wet spring weather.
Why is my smyrna quince brown rot (monilinia fructigena)?
Fruit rots on the tree, often with concentric rings of white spore pustules. Remove and dispose of all mummified fruit; ensure good air circulation through pruning.