I don't think alyssum would do well in shade but how about browalia and/or torenia? There are others but not that I can think of at the moment.

I planted Osteospermum in my front garden last year (morning sunlight only), and (surprisingly) it did well enough, though I'm sure it would have preferred a sunnier spot. I also had great success with Morning Glory in the same spot, though it didn't grow as high as I'd hoped. Finally, I'd certainly suggest that you try some Scizanthus if you haven't considered these plants -- they're just spectacular, thrive in cool, moist, and shady locations, and provide beautiful colour for me from May to September in my Peace River, AB garden.

Schizanthus is good and so is mimulus.

Thanks for the suggestions! I've grown Scizanthus before but I thought it needed full sun. Will have to start growing it again. I love the flowers. I looked up muimulas and they might be worth a try too. Marg

Try Garden Balsam (Impatiens balsamina). Nicotiana will bloom nicely in part shade. I have self-seeding patches of annual Candytuft (Ibiris umbellata) that do just fine with not much sun.