Troubleshooting
Filbert 'Barcelona' problems — and how to fix them
Filbert 'Barcelona' (Corylus maxima 'Barcelona') 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.
Eastern filbert blight
'Barcelona' is highly susceptible to this fungal disease (Anisogramma anomala), which can kill trees. In affected regions choose resistant cultivars or prune out and destroy cankered wood promptly.
Requires a compatible polleniser
Hazels are self-incompatible and need a separate variety with overlapping pollen shed (such as 'Hall's Giant') to set nuts; a lone tree crops poorly.
Heavy suckering
It suckers vigorously from the base, especially when grown as a single-trunk tree. Remove suckers regularly to maintain form and direct energy to cropping wood.
Squirrels, filbertworm and bud mite
Squirrels take nuts, filbertworm larvae infest kernels, and big bud mite distorts buds. Monitor, harvest promptly, and clear fallen infested nuts and prunings.
Prevent filbert 'barcelona' problems before they start
Most filbert 'barcelona' issues are care-mismatch, not bad luck. Dial in the basics:
Looking for filbert 'barcelona' in general rather than its problems? Read the full filbert 'barcelona' care guide — light, water, soil and feeding.
Filbert 'Barcelona' problems — FAQ
Why is my filbert 'barcelona' eastern filbert blight?
'Barcelona' is highly susceptible to this fungal disease (Anisogramma anomala), which can kill trees. In affected regions choose resistant cultivars or prune out and destroy cankered wood promptly.
Why is my filbert 'barcelona' requires a compatible polleniser?
Hazels are self-incompatible and need a separate variety with overlapping pollen shed (such as 'Hall's Giant') to set nuts; a lone tree crops poorly.
Why is my filbert 'barcelona' heavy suckering?
It suckers vigorously from the base, especially when grown as a single-trunk tree. Remove suckers regularly to maintain form and direct energy to cropping wood.
Why is my filbert 'barcelona' squirrels, filbertworm and bud mite?
Squirrels take nuts, filbertworm larvae infest kernels, and big bud mite distorts buds. Monitor, harvest promptly, and clear fallen infested nuts and prunings.