Similar in overall appearance to the border types, but with smaller leaves and usually much narrower flowers, specialist penstemons include low-growing ‘subshrubs’ that have woodier stems and flower mainly in summer (some do start in spring). Some are true alpines and really need extra care.
These compact, usually evergreen subshrubs and alpines vary from upright to more spreading, prostrate or mat-forming plants. Tubular white, pink, red, blue or yellow flowers are borne over several weeks. Examples are Penstemon fruticosus var. scouleri 'Albus', Penstemon newberryi and Penstemon rupicola.
These more specialist penstemons must have free-draining, ideally gritty soil in full sun. They can do well in poor soil. In cold areas, they appreciate the protection of being planted at the base of a warm wall. A gravel garden, scree or rock garden would be perfect.
Plants will not do well in heavy, wet soil and will not flower in shade.
Did you know?
To keep plants compact and productive, shorten stems immediately after flowering. Delay pruning of late-summer-flowering types until early spring.
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