Reduce flies

I read that used coffee grounds when lighted will deter flies and mosquitoes , I decided to try it but I did not light it as I dont like the smell of burning coffee
so I have been placing used fresh coffee grounds in a little bowl In the kitchen and verandah and for a few weeks now l havent seen hardly any flies .
I put 2 plants by the coffee and within a couple of weeks they grown and flowered they are impatiens as pic shows
Also a few weeks ago when we had nice weather the dustbin was hot and starting to smell so I thought what could I use to cover the bin and stop the flies?
So I covered the top and sides with brown paper not only did keep the bin ..cool but it reduced lot of flies

 

That's interesting Janet. Useful to know .
Thanks.