sounds as if these are scarid flies that live in damp compost. If i get them on other plants i let the plant dry out as much as i dare to kill the beggars off.
dont know how dry an orchid can get though.

That is what I thought they were,Sbg..and I have tried to let them dry out as much as I dared..but thanks for your input..I thought I would have trapped them all on the sticky sticks,but they obviously aren't attracted..

What sort of orchids are they Bloomer? The compost for something like a phal should be such that it doesn't really retain water.

They are both Phals,Mg..and in the correct compost..so yes,very free draining..and I don't let them stand in it,after watering,which isn't often at the moment....I wonder if they have been transmitted from other cuttings and plants,? as I do move them to the Conservatory when it's warmer,where I grow things on..or stand them outside in a shaded area when ..I repeat when, we have some hot summer days ..!
Thay are more annoying than anything...

I grow a lot of my orchids i.e. vandas and phals in jars without compost as you can then see the roots and monitor the watering. You could take them out of their pots and dry out your compost completely to kill the flies, then replant them if you want to. They grow on trees in the wild ,I think the compost/bark is just to keep them stable in a pot

That sounds interesting Jenfren,thank you...I can see the logic in the compost being for stability..I have a bag of new Orchid compost,so it might be a better idea to throw the old stuff away,and start again..I would use the same size pots,as they aren't ready for repotting for a while yet..
One of them is quite special to me,as it was bought as an Anniversary present 8 years ago...

Good idea if you have orchid compost to just empty the pots out wash the roots off and repot, having given the pots a good scrub. I agree Jen the compost is just to keep the orchid stable.

Thank you Mg..I will follow yours and Jenfrens advice...much appreciated ...

Let us know how you get on...

Will do..thanks ..

just a little blast of fly killer wont hurt your plants as fly killers effects the insects central nervous system and plants dont have one .

Except you'll be breathing it in too NP, better to sort the problem.

doesnt all fly spray get sprayed in your house ?

I never ever use any fly spray in the house... In fact I avoid all aerosols as far as possible.

well thats yuor perogative mg but im quit sure fly spray is pretty safe or they couldnt sell it .

You keep on believing that NP! There are tank loads of harmful chemicals sold that should not be. Try a fly swatter good fun and exercise :-)

well im actualy asmatic and dyslexic and feal fine considering all the nasties we did live with 50 years ago like lead in paint,aspestoss etc plus ive never heard of anyone ding of fly killer inhilation . have you ? also with england urning like america ie wear theres a blame theres a claim companies cant affod t murder there ustamers realy so i will do as you say for once lol and keep believing that . you have a lot more bad things out of a car egsaust so id guess you walk everywear or wear an air filtering mask lol xx.

Nope live in a very rural situation... this is way off topic now NP so I suggest we agree to disagree.

well its the easiest way out so be it .

An update on the flies...pleased to say,the sticky insect traps have done their job..once they decided to investigate...There are about 12 of the little B's on the one's on the Orchids,so I'm pleased about that...I also put one in each of the pots of overwintering plants in the Conservatory..luckily,I haven't so many this year....but there were quite a few flies on those too ...hopefully they are now fly free :o) .Thanks for your advice..much appreciated..

your welcome

Many thanks Moon_growe for tips on black flies on orchids. Mine is suffering the same fate but totally agree about the spraying - don't unless you absolutely have to. The aerosols are absolutely full of chemicals, as is much that is on sale today. There are links to certain types of cancers, Alzheimers etc. I never ever spray - we have apples, raspberries, blackcurrants, gooseberries etc but never spray unless its a mild solution of washing up liquid diluted in water. Sometimes works, sometimes not but if I lose a few fruit so what - rather that than spraying goodness knows what on them and then eating it !

Agree Siouxsie, much better to lose a few fruits than eat pesticides!