'Midnight Blue' Beard-Tongue
aka, Purple Border Penstemon
"Strew the flowers at Love's behest
Meet for such a lovely guest."
-Frank S. Williamson
(1865-1936)
(1865-1936)
The cultivar name 'Midnight Blue' is sometimes given as 'Midnight.' This shrub-like semi-woody perennial has dark purple flowers & evergreen foliage. The older upright stems turn red-orange in autumn, so that it has an attractive presence even when the long bloom period of summer to mid-autumn is over.
It is a hybrid of P. strictus or Rocky Mountain Beard Tongue native of the American southwest, crossed with Border Penstemon, P. gloxinoides.
It is not necessary to fertilize penstemons. The three or four years that it is in its prime might be extended to five if it is never fertilized. They bloom just as well without fertilizer, whereas with it they more quickly become huge leafy clumps & wear themselves out.Most penstemons are best replaced after three or four years. New ones are easily started from cuttings taken in autumn, rooted indoors, & put out in spring to supplant exhausted clumps. Although they may self-seed to remain in the garden without attention, seedlings do not ordinarily grow to be exactly like the parent plant.
Or a tired clump can with varying degrees of success be refreshed if it is dug up, divided, & new clumps started, although often enough, the divided parts don't recover to best effect. Ideally fresh plants are started from cuttings for the most certain results, or can just be replaced by nursery-started youngsters, which simultaneously presents the option of a given spot having a completely different variety every few years.
Prone to root-rot in our wet winter weather, perfect drainage is a must, & it is sometimes recommended to keep mulch off them, or to mulch only with gravel. As our climate is especially temperate, mulching is not at all necessary, but sharp drainage is an absolute requirement.
Penstemon 'Ruby' or 'Schoenholzeri'