I'm not sure which geranium you are referring to as cranesbill is a common name sometime used for any geranium. Some need sun to bloom, some are not so drought tolerant. I think the best one for dry shade is geranium macrorrhizum (there are several varietys -- all good). This is a vigorous geranium and very tolerant of almost any conditions.

I think there are many species that would do. I have many kinds in a bed that gets less than four hours sun. I think most if well watered until established would tolerate dry. My bed gets no additional water.

The common wild geranium up here in the NE is geranium maculatum, and although it is fine in dry soil, it need a fair amount of light. It grows in the verge of the denser woods, and in open shade areas. A lovely native wildflower.

George

It's a very good choice. Mine has taken over other plants on a raised bed under a maple tree. I am actually moving it to a very difficult spot in the front lawn- full sun, baking dry poor clay.
There are many varieties- some have nice fall colour too.

Thanks everyone!

I am mainly looking at G. macrorrhizum, I want something that gets big with lots of color. Once the trees leaf out it will just be a little morning sun.

Jen