do you want perennials or annuals, climbers like clematis, jasmine and honeysuckle would love the sun,
have you got any trees or walls for them to grow up,
I love things like mesembryanthemum? spelling.. open during the sunny bits and cover the ground quite well, lavenders, we tend to stick with perrennials as they look after themselves when they're established,
I also like periwinkle , tall maltese cross, dicentra or bleeding heart's a beautiful plant
I'm not sure about seed for some of them,
hope this jumbled tirade helps a bit ;D