Dave's Garden PlantFiles - Profile page with horticultural basics, and member-contributed photos and comments. (2 photos)
Heritage Perennials - Profile with description and horticultural details. (zone 5-9) (1 photo)
Lady Bird Johnson Wildflower Center - Plant description and characteristics with notes on distribution, culture, and propagation. (2 photos)
Rainy Side Gardeners - Plant profile compiled by two gardeners in the Pacific Northwest. Includes propagation and pruning methods, and commentary. (zone 6-8) (1 photo)
(2 photos)