What's eating my mizuna?

Mizuna's feathery, soft leaves are irresistible to flea beetles from spring through early autumn — tiny holes appear almost immediately after emergence. Slugs are a major problem in cool, wet conditions, particularly in UK autumn sowings. Cabbage white caterpillars and aphids follow in summer. Fast growth gives mizuna some ability to outrun light pest pressure.

Characteristic shot-hole damage across leaves from seedling stage; fast-maturing mizuna can outgrow light attacks but heavy pressure stunts or kills crops entirely. Insect-proof mesh netting from day of sowing is the most reliable control. Avoid spring sowings at peak beetle flight if possible. Companion-plant with tall crops to create partial shade, which reduces flea beetle activity.

Irregular holes with slime trails on lower leaves and leaf bases; seedlings can be severed at soil level; worst in autumn and after rain. Iron phosphate pellets (Ferramol/SlugGo). Beer traps sunk to soil level. Clear debris around beds. Avoid over-watering which creates ideal slug habitat.

Larger caterpillars eat rapidly through mizuna's thin leaves; summer sowings without netting can lose an entire bed in under a week of heavy caterpillar activity. Insect-proof netting prevents egg-laying. Bt spray on visible caterpillars in the evening. Hand-pick when populations are low.