No, this is certainly not a particularly shaded site from the sounds of it. I think from your description you will not be that restricted with your plant choice either having the best of both worlds. Sun for the first part of the day but not the hottest part of the day. You may well be able to grow plants from a wide spectrum, sun lovers through to part shade. The fact that its not in full sun later in the day is ok for most sun lovers as vertical walls don't cast overhanging shade being open to the bright blue yonder above......unless its collapsing!

Some helpful plant labels or websites tell you how many hours of sun a plant needs. It's a difficult area to describe, I agree.

I'd go by the 'hours of sun' idea.....roses need a mimimum of 5 hours of sun, for example!

Seems I must look at the unhelpful labels, websites & books as they always seem to categorise by full sun, partial shade or shade ;-(

the 'number of hours of sun' seems a great way of describing the plants needs - which website(s) gives this indication ?

I'd consider the circumstances you're describing as part sun, part shade - many plant labels do describe in this way. Whatever you do choose to plant, don't choose a Camellia - east facing is the one thing it won't do well with in terms of flowering.

Thanks for the responses - things I am considering for this area are campanula, knautia, allium, geum (sp?) - would be good to get a bit of colour there - any thoughts ?

Campanulas should do well, knautia requires full sun, but might be worth a try.