Troubleshooting
English Walnut 'Tulare' problems — and how to fix them
English Walnut 'Tulare' (Juglans regia 'Tulare') 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.
Walnut blight
Xanthomonas arboricola bacterial blight blackens catkins, leaves and young nuts in wet springs. Copper sprays at budbreak and during bloom, plus open canopy pruning, reduce losses.
Codling moth
Larvae bore into developing nuts, causing drop and kernel damage. Monitor with pheromone traps and time controls to egg hatch; sanitation of fallen nuts lowers carryover.
Crown and root rot
Phytophthora attacks trees on heavy or poorly drained soil. Plant on a berm with excellent drainage and avoid wetting the trunk base during irrigation.
Spring frost damage
Though 'Tulare' leafs mid-season, an unusually late frost can kill emerging shoots and flowers, cutting the crop. Avoid frost-pocket sites for reliable yields.
Prevent english walnut 'tulare' problems before they start
Most english walnut 'tulare' issues are care-mismatch, not bad luck. Dial in the basics:
Looking for english walnut 'tulare' in general rather than its problems? Read the full english walnut 'tulare' care guide — light, water, soil and feeding.
English Walnut 'Tulare' problems — FAQ
Why is my english walnut 'tulare' walnut blight?
Xanthomonas arboricola bacterial blight blackens catkins, leaves and young nuts in wet springs. Copper sprays at budbreak and during bloom, plus open canopy pruning, reduce losses.
Why is my english walnut 'tulare' codling moth?
Larvae bore into developing nuts, causing drop and kernel damage. Monitor with pheromone traps and time controls to egg hatch; sanitation of fallen nuts lowers carryover.
Why is my english walnut 'tulare' crown and root rot?
Phytophthora attacks trees on heavy or poorly drained soil. Plant on a berm with excellent drainage and avoid wetting the trunk base during irrigation.
Why is my english walnut 'tulare' spring frost damage?
Though 'Tulare' leafs mid-season, an unusually late frost can kill emerging shoots and flowers, cutting the crop. Avoid frost-pocket sites for reliable yields.