Color: Purple Flower Size: 4-6″ (10-15cm) Flowering Period: June-Sept Mature Height: 8-12′(2.5-3.5m) Pruning Group: B2 or C Planting Aspect: Sun/ Partial Shade USDA Zone: 3 Foliage: Deciduous Suitable As Ground Cover: Yes Price Group: Standard About Serenata Dusky-purple with contrasting yellow stamens. 4-6″ (10-15cm) flowers from June to September. Mature height 8-12′ (2.5-3.5m). Pruning group B2 or C.