What do bees actually do with these houses? I've had a couple of bees going in and out of them in my garden
I suppose they have two or three different uses. In the winter, insects of all types could use them as a hibernation roost. In summer, solitary bees could use them as a place to lay an egg. Spiders could use them all year round as a place to hide and lie in wait for prey.
Lots of fascinating info here http://www.foxleas.com/bee_house.htm
I get two distinct populations in mine, masonry bees in the early part of the summer and when they hatch out I get leafcutters who seem to take their building material from a standard willow in the garden. I love watching the speed at which they can chop out their half circle!
I put mine up according to google, the opening faces almost due south and gets morning sunshine, actually it gets sunshine for most of the day.
mine is about 8inches off the ground and has three holes 'leaf filled' on an east facing wall but i have also seen a full up one at top of fence height 4/5 ft.
I found one trying to use the keyhole in the shed the other day. And they love the little holes made for the dowels underneath the garden table top - the idea of bees flying up your skirt is not a comfortable one.
Oh yes, I didn't say that it is at top of a 6' fence.
Bumblebees like to be at ground level I believe.
There is a hole in the ground at the end of my allotment which bees have been flying in and out of for a couple of months. I noticed this week that all activity has stopped. Does anyone know what they were actually using the hole for?
They will have been nesting. They move on when they feel like it.
Something to mention is that boxes like the one pictured with a thin exterior wall are, as I understand it, best moved somewhere sheltered for the winter as they aren't insulated enough to stop the larvae freezing to death as they overwinter.