Peony Collection This superb Peony Collection includes varieties of ‘Sarah Bernhardt’, ‘Karl Rosenfield’ and ‘Shirley Temple’. They are all double blooming peonies that produce masses of flowers from May until June. Paeonia lactiflora are hardy perennials that are key staples in traditional cottage gardens, however, they do also look superb grown in wildlife gardens, contemporary gardens and cut flower gardens. As time progresses, your Herbaceous peony will mature and each flower will grow bigger and better than the year before. This Peony Collection is easy to care for and grow; each Peony requiring sun and semi-shade to reach its optimum level.