It is the cri de coeur of gardeners far and near: "What grows in the shade?" Surprisingly plenty, although it requires much peering at plant labels in the garden centre to determine which annuals are candidates for shadowed installations.
Unfortunately, we must give a pass to that great old standby, Impatiens. Overuse has made them almost certainly to succumb to an unpleasant and all-pervasive pathogen. Many retailers will not even stock them or else warn customers of the hazard.