Flea beetle

Very small shiny black beetles sometimes with a yellow stripe running along each wing case. They eat small, circular holes on the upper leaf surface which result in the leaves looking like they have been shot through with tiny pellets. Know more about Flea beetle

Protect

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Cultural measures: Remove all plant debris. Thoroughly prepare soil before planting.  Protect seedlings through the vulnerable seedling stage by sowing when weather conditions allow rapid germination, protecting seedlings and young plants with fleece until established.  Delay planting out young brasica plants until more established to reduce the chances of the young brassica plants being too severely damaged by these beetles.