Found the cause, thanks. Some dead worms from where I'd been digging out the borders and cat poo that was hiding under some leaf litter. I removed as much as I could and sprayed bleach algae to mask the smell. There are still some bluebottles in the garden tho, I'll have to do a proper tidy up with gloves on when kids' dad is at home.
Hi, I hope I'm posting in the right place for advice.
I've recently attacked the overgrown jungle-like borders in my back garden, thought is done a really good job. From the window it looks great: short grass and clear borders which I have seeded so that grass will grow right up to the fences.
I've done this because I'm not a gardener and want the space to be nice but easy to maintain and user friendly, an area where my children can play out happily and safely.
However, there is a problem. I went out this morning to hang out the washing and to pick up any weeds that might threaten to start taking over and undo my hard work, but when I got to the top of the garden there were loads and loads of flies.
They were blue-ish in colour and were landing and resting on the leaves that had fallen off the rhodedendrum (sp?) bush and the petals that had fallen from another tree close by. Some of these leaves are black, I think the bush is deseased as there are loads of black leaves on it as well as the ground. I plan on digging it up.
The area is damp (but not waterlogged) and shaded if that makes any difference. There are plums around that have fallen from the plum tree, but these flies were not bothered about them.
I just want to know what they are: they look like bluebottles but there's nothing dead apart from the vegetation. Are they in any way dangerous, are they going to be here all the time or will they go of their own accord, or shall I get rid of them? And if so, how? I don't have a lit of money to spend on equipment to get rid, I have 2 small children so have limited time available to spend on the problem and am reluctant to use anything poisonous.