Desperate for help with leafminers

[elight]

I have a variety of in-ground and container plants that have been consumed with leafminers this fall. I keep removing affected foliage, but it doesn't seem to slow them down and some plants are almost bare at this point. The container plants seem to be the hardest hit. I am guessing that some past insecticide spraying in a previous season or at the beginning of this season (honestly can't remember) might have killed a natural predator; lesson learned.

What's strange is that I also have two containers with lettuce and herbs planted away from the tomatoes, on my pool deck and inside my pool enclosure. I've just noticed some leafminer activity in those as well.

So, some questions:

1. Is it possible the leaf miners came from my grow media? Although none of the ingredients in my raised beds (compost/vermiculite/peat) are shared with the containers (pine bark/perlite/peat-based mix).

2. I ordered some parasitic wasps out of desperation. Has anyone had success with these? Do I need to do more than one release of them to be effective?

3. Is there anything else I can do this season, or anything I can do for the spring season, to prevent this from happening again (other than not using the insecticide)?

Thank you!