Troubleshooting
Fertility pear problems — and how to fix them
Fertility pear (Pyrus communis 'Fertility') 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.
Pear scab (Venturia pirina)
'Fertility' has moderate susceptibility to pear scab. Dark scabby lesions on fruit and leaves reduce marketability and may cause fruit cracking. Apply copper oxychloride or approved fungicide at green cluster, white bud, and petal fall, and remove fallen leaves in autumn.
Pear midge (Contarinia pyrivora)
Fruitlets turn black and fall early in June; larvae feed inside. Cultivate soil under the tree in winter to expose pupae to frost and birds. Apply a suitable insecticide (deltamethrin) at white-bud stage if infestation was severe the previous year.
Over-cropping and biennial bearing
'Fertility' can set very heavy crops, leading to small fruits and a biennial (every-other-year) bearing pattern. Thin fruits to one per cluster by late June (June drop plus hand thinning) to encourage annual, quality cropping.
Prevent fertility pear problems before they start
Most fertility pear issues are care-mismatch, not bad luck. Dial in the basics:
Fertility pear problems — FAQ
Why is my fertility pear pear scab (venturia pirina)?
'Fertility' has moderate susceptibility to pear scab. Dark scabby lesions on fruit and leaves reduce marketability and may cause fruit cracking. Apply copper oxychloride or approved fungicide at green cluster, white bud, and petal fall, and remove fallen leaves in autumn.
Why is my fertility pear pear midge (contarinia pyrivora)?
Fruitlets turn black and fall early in June; larvae feed inside. Cultivate soil under the tree in winter to expose pupae to frost and birds. Apply a suitable insecticide (deltamethrin) at white-bud stage if infestation was severe the previous year.
Why is my fertility pear over-cropping and biennial bearing?
'Fertility' can set very heavy crops, leading to small fruits and a biennial (every-other-year) bearing pattern. Thin fruits to one per cluster by late June (June drop plus hand thinning) to encourage annual, quality cropping.