Troubleshooting
Sea Beet problems — and how to fix them
Sea Beet (Beta vulgaris subsp. 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.
Leaf miners (beet leaf miner)
Larvae of Pegomya hyoscyami tunnel within leaves, leaving pale blister-like tracks. Remove and destroy affected leaves; fine mesh covers prevent egg-laying on outdoor plants.
Powdery mildew
White powdery coating appears on leaves in warm, dry conditions with poor airflow. Improve spacing and ventilation; water at the base rather than overhead to reduce humidity around foliage.
Downy mildew
Pale yellow patches on upper leaf surfaces with grey-purple fuzz below, worse in cool, damp weather. Remove infected leaves and avoid wetting foliage; resistant varieties are preferable.
Prevent sea beet problems before they start
Most sea beet issues are care-mismatch, not bad luck. Dial in the basics:
Sea Beet problems — FAQ
Why is my sea beet leaf miners (beet leaf miner)?
Larvae of Pegomya hyoscyami tunnel within leaves, leaving pale blister-like tracks. Remove and destroy affected leaves; fine mesh covers prevent egg-laying on outdoor plants.
Why is my sea beet powdery mildew?
White powdery coating appears on leaves in warm, dry conditions with poor airflow. Improve spacing and ventilation; water at the base rather than overhead to reduce humidity around foliage.
Why is my sea beet downy mildew?
Pale yellow patches on upper leaf surfaces with grey-purple fuzz below, worse in cool, damp weather. Remove infected leaves and avoid wetting foliage; resistant varieties are preferable.