Penstemon digitalis Dark Towers - Foxglove beardtongue

The Penstemon 'Dark Towers' is a superb American variety related to the famous 'Husker Red', which surpasses with its larger size and darker foliage colour that does not fade during hot summers. This beautiful penstemon offers dark purple evergreen foliage with burgundy stems adorned with soft pink campanulate bell-shaped flowers with a dark pink base. This perennial plant is reliable and probably one of the hardiest penstemons in well-drained soil. Its elegant and delicate flowering is perfect for borders and flower beds from June to October. It can be grown in all gardens, in well-drained soil, in full sun.

The Penstemon digitalis belongs to the family of Scrophulariaceae, just like the foxglove with its similar flowers. But while the latter is European, the 'digitalis' penstemon is of American origin. It is mainly found in the eastern and southeastern United States, growing in dry areas such as meadows or open forests on well-drained, loamy or sandy soil. The variety 'Dark Towers' was obtained by Dr. Dale Londgren from the University of Nebraska, a specialist in Penstemon. It is said to be a cross between the 'Husker Red' variety and the Penstemon 'Prairie Splendor', both created by Longdren. 'Dark Towers' develops from a robust base, forming a basal rosette of large evergreen leaves with a shiny purple top and wine-red underside. In spring, leafy stems of burgundy colour rise, reaching a height of about 80 cm (32in). They bear numerous tubular flowers with a soft pink colour at the base and a dark pink, grouped in pairs. This variety is one of the hardiest in healthy soil and tolerates dry shade well.

The 'Dark Towers' penstemon is used in borders and perennial flower beds with agapanthus, caryopteris, Rhodoanthemum hosimariensis, and Cape daisies or mixed with annuals such as love-in-a-mist. Its delicate flowering complements the round corollas of old roses (Salet, Yolande d'Aragon). It can blend among the rocks in rock gardens (in slightly non-chalky soil) with rosemary, cotton lavenders, cistus, or wormwood. It also performs very well in pots, with proper drainage and regular fertilization. Penstemons also make excellent cut flowers.