Oh.... if you think Limelight is bad, try Quick Fire!!! QF seems to attract 10 times more flies than Limelight! I don't think it's necessarily a bad thing, but it just happens... you have not noticed any damage to the plant, have you? Just checking that you're not referring to anything else that may be bad...

I think all H paniculatas with fertile florets attract pollinators including flies ... they are particularly, magnets to all the flying critters small & big. They don't usually bother anyone, as they are too busy collecting their food supplies for Winter (saving for the rainy days - so to speak!!!) &&&&& too drunk, to be interested in humans!!! They usually come, once the tiny florets flash open.

I've noticed that different flowers, attract certain kinds of flying bugs more than others ... even those tiny guys have their favorites. The black hornets (I fondly call, top guns) seem to prefer all the H paniculatas with fertile florets, I have around ... QF as the earliest to flash is in charge of the 'bugle call' LOL!!!

Thanks for the responses. I was hoping they weren't doing harm. It's just that I never noticed them last year.

They're not doing harm. Flies, among them many beneficial kinds, visit flowers to obtain pollen which provides protein the flies need before they can lay eggs.

I pulled up this thread because I have the same problem and I was looking for a solution. I have a small yard too and I put a few limelight hedges in for privacy. When my hedges were young i had no flies but now that they're a few years old flies galore (mostly house flies). Because my yard is small I feel like I'm up close and personal with the flies when I sit outside. Is there really nothing I can do about it?

You could try attracting birds to the area. Maybe put a bird house or bird feeder.

Why not it can't hurt! I'll give it a try. Would citronella candles work?