Flies

I wouldn't think it was anything to do with the clematis joysie21, the flies are probably just drinking from the pond & you could have mosquitoes laying eggs in the pond if it's fairly still. There seem to be lots of flies around this year, I keep walking into the greenhouse & finding it full of big black flies so that I look around to see if anything is dead or smelling off in there but I think they just like to shelter in there from the rain! If you sit near the pond & the flies bother you there are citronella candles you can light which supposedly deter flies/gnats/mozzies etc.

It's funny you should mention that @joysie, 'cos I was just thinking the other day that we've had almost NO flies up on the Roofgarden this year.

As to how to solve the fly infestation... ummm.... rent a frog ?

Roofy all your flies must be on holiday up here, even my O.H. said today that there seem to be a lot around outside today! I think it must be because of all the standing water in the field at the back of us & the warm weather we've had earlier this spring.

Yup... no flies, and no blackfly or greenfly, no ladybirds, and no butterflies !!!
And very few wasps !

Because of my lack of bedding plants this year, I've only seen cabbage whites flitting about, but every time the back door is left open, the blow flies come in. My remedy is to shut them in the utility, where they get overheated in the afternoon sun, and are only too happy to go out the window a little later

Erm.... more like 'a fly without wings, would be a walk!' sweetpea

There are flies and there are flies! Incredibly diverse group of insects. Need pics abd typical behaviour traits to discerne which they are. Many stocky "typical flies" that look like houseflies, bluebottles etc are often members of the fly family Tachinidae (parasite flies). These do as much of a service in the garden as the unrelated Ichneuman wasps both in parasitising caterpillars and other insects as well as pollination.