Filmed 23rd May, two months after planting out small seedlings of multisown onions.
This is a new pest here since 2023, Phytomyza gymnostoma. It is proving difficult!
I plan to remove the cover in early June.
In the UK I buy covers from Gardening Naturally gardening-naturally.link/gr8kv#nodig#leafminer#onion#gardenpests#growingvegetables