How to get rid of flying insect pests...
 

This is the best control for flying insect pests that I found...
Using sticky traps! I use the specific one called Safer Brand Houseplant Stick Stakes. They control whitefly, blackfly, thrips, fungus gnats, fruit flies, midges, and most other flying insects. You can usually buy this specific trap at Earl May or at: Amazon.com: House Plant Sticky Stake 7 Pack: Patio, Lawn & Garden
I've used them and they work very well. I keep a few sticky stakes around my plants continuously.
Let me know if these work for you...

I have seen these in greenhouses - haven't tried them myself, but looks like they help a lot!

i have a giant nepenthe do all the work for me even eats stink bugs.

I have three venus fly traps that also help. Research carnivorous plants before you buy them if you buy them. They are definitely unique in their requirements...

i can grow many things i have a greenhouse

Love the pitchers. Took care of a few flies and some other larger bugs. I have just one right now and a butterwort but am on the prowl for a sundew. A trap for each size of insect. I hope these won't prove too addicting. : )

I have used Fly Ribbon and do a fog with a mix of rain water, mild dish soap and alcohol in my sprayer every few days, this is keepping the flying insects at bay.