Black flies infesting greenhouse – What can I do?

Black flies infesting greenhouse – What can I do?

Unfortunately, I was unable to go and collect tomatoes from my greenhouse for a couple of days, and when I did go in, lots of the tomatoes had split, and there were little swarms of big black flies (they may have been fruit flies?) feeding on them. I picked all the split and moulding tomatoes, and threw them away, but, unfortunately, the big black flies have stayed. Just looking at them makes me feel sick =/ I wonder if lots of black fly eggs have hatched in there. Anyway, I have tried scaring them out, but to no avail, every morning they are back. Any idea how I can get them out for good? Thank you!!!!
New room plans

New room plans

Marigold seeds

Marigold seeds

Shots of my room

Shots of my room

Muchoo help needed puh-lease. **UPDATED**

Muchoo help needed puh-lease. **UPDATED**

Does anyone else encourage “weeds?”

Does anyone else encourage “weeds?”

A question of bugs.

A question of bugs.