Troubleshooting
Sea Kale problems — and how to fix them
Sea Kale (Crambe maritima) 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.
Crown rot in wet soil
Heavy, poorly drained ground rots the perennial crown over winter. Plant on a free-draining site with added grit, and never let water pool around the base.
Cabbage-family pests
Flea beetle, cabbage white caterpillars and slugs all target the leaves. Net young plants and check the undersides of leaves; the waxy bloom gives some protection.
Over-forcing weakens crowns
Forcing blanched shoots every year without recovery exhausts the plant. Let crowns build reserves through summer and skip forcing entirely every third year to keep them vigorous.
Bolting and slow establishment
Seed-raised plants are slow and variable, often taking two to three years to crop. Thongs (root cuttings) establish faster and crop more reliably.
Prevent sea kale problems before they start
Most sea kale issues are care-mismatch, not bad luck. Dial in the basics:
Looking for sea kale in general rather than its problems? Read the full sea kale care guide — light, water, soil and feeding.
Sea Kale problems — FAQ
Why is my sea kale crown rot in wet soil?
Heavy, poorly drained ground rots the perennial crown over winter. Plant on a free-draining site with added grit, and never let water pool around the base.
Why is my sea kale cabbage-family pests?
Flea beetle, cabbage white caterpillars and slugs all target the leaves. Net young plants and check the undersides of leaves; the waxy bloom gives some protection.
Why is my sea kale over-forcing weakens crowns?
Forcing blanched shoots every year without recovery exhausts the plant. Let crowns build reserves through summer and skip forcing entirely every third year to keep them vigorous.
Why is my sea kale bolting and slow establishment?
Seed-raised plants are slow and variable, often taking two to three years to crop. Thongs (root cuttings) establish faster and crop more reliably.