Unfortunately, our group cannot answer your question because it doesn't serve your location. Please contact your local Cooperative Extension office for assistance. A good way to find your local office is to go to https://extension.org/search/ and enter your county or parish name along with your state name. You might also use your favorite search engine and enter "cooperative extension" along with your county name.

(To get you started, you can learn about the Allium Leafminer life cycle on the linked UMD page. However, since the details of life cycle timing can vary from locations in Maryland and Virginia, and planting dates may also vary for those vegetables, we recommend you check with local VA Extension resources to verify what actions are the most likely to protect the crops from ALM damage. Generally, covering them after planting with insect mesh netting and leaving it in place until harvest is probably the most practical approach, since that does not rely on weather or other factors influencing a planting date or insect emergence date.)

I have contacted my extension office. and have spoken at least twice with their agent who suggested articles for my review - hence my contact to you. Other than covering

A cover barrier for the egg-laying adult flies is considered an organic approach, as would be using an organic pesticide (spinosad, potentially, depending on how it's labeled) once egg-laying scars are seen on the foliage (which should only happen if a cover wasn't used, especially for the second generation emerging in autumn). If you were to plant after the second adult flight and mating period is over (around November in central Maryland), you could forego the row cover for a time, but then would need it in spring to reduce the risk of a spring infestation.

Miri