If you're looking for an easy-to-please shade-loving perennial that flowers its head off in spring, Primula sieboldii is hard to beat. It comes in many forms, all of which spread into good-sized clumps that send up rounded clusters of large flowers that range in color from white to pink to purple to blue. Grown from seed from the famed Barnhaven primrose nursery in France, plants in the Smooth Pink Shades seed strain flower in a range of deep- to pale-pink hues, with smooth petal edges. All forms of the species go dormant in summer. Photo: Barnhaven