How can you possibly choose? There are about 280 species of penstemons found from Alaska to Guatemala plus selected and named cultivars of many species as well as hybrids between two or more species.
Varieties that are most popular and successful around Santa Fe feature tall spires of red, pink and purple or blue and are relatively drought tolerant. There are a number of reds. P.eatonii is the earliest, reliable and easy. P.pseudospectabilis has pendant magenta flowers on spreading stems and P. cardinalis is not a cardinal red, but a deeper more unusual shade. P. barbatus has slender flowers on erect stems for long bloom from mid-summer until fall.
The best pinks are P. palmeri, which also has a delightful honey scent that attra
cts bumblebees, and P. clutei, a rugged species from northern Arizona with especially attractive, toothed gray-green foliage with a mauve tone over the winter.
P.angustifolius is also early and may be lavender, pink or pale blue. P. strictus may be various shades of deep blue to purple and is a most reliable and fast increasing species. It may even bloom the first year from a 4" pot.
For a beautiful display next June, buy plants in 4" pots and set them out in a sunny spot where you have damp soil that is lean, sandy loam. Dig deeply and mound the removed soil, after it has been broken up and mixed, in the hole. Wash plant roots in room temperature water to remove most of the potting mix and spread the roots evenly over the mound, holding the crown just above the outer soil level, firming additional soil over the roots to the outer soil level, and watering in each plant immediately. They will thrive with 12 - 14" of precipitation a year. Infrequent watering will be required the first year if natural moisture does not occur regularly. (The thrifty gardener will purchase seeds of these varieties to scatter in late fall producing seedlings for transplanting the following spring.)
Smaller penstemons that are popular and do well in Santa Fe are: P. virens, an early bloomer with clear sky blue spikes about 8" tall; P. linarioides, which forms a mound of silvery, needle-like foliage that is attractive all year, producing many short spikes of pale blue-lavender flowers in May; and, P. pinifolius with short stems of slender, scarlet flowers for a long display from late spring through summer. There are also yellow variants of P. pinifolius with paler green foliage than the red species and recently an orange variant. These are reliable plants that may be almost blooming size in 4" pots, and if planted early in well prepared, lean sandy loam may put on a show the first year they are in your garden.
For those who can't wait, transplant large plants of Midwestern and Eastern species and some hybrids from gallon nursery containers in late March and early April into a perennial bed with good but not too rich soil. Water regularly and they will thrive and bloom in June or later. Some of these available in local nurseries are Penstemons digitalis 'Husker Red', a tall, erect cultivar with white to pink flowers and deep mahogany-red stems and foliage, 'Elfin Pink', a coral to pink-flowered hybrid and two new Mexicali Hybrids, 'Red Rocks' and 'Pike's Peak Purple'.
Learn more about others from the American Penstemon Society's book Growing Penstemons: Species, Cultivars and Hybrids, $17.95, obtainable from nurseries or Ellen Wilde, 982-1406.