Penstemon is a perennial with more than 250 species primarily found in North America. Although a great percentage of these are indigenous to the western states, a few are native to the central and eastern U.S. Cultivating species Mother Nature has planted is one way to increase the chance of a garden plant’s survival in this uncertain climate of ours.
Commonly known as Beardtongue, Penstemon begins with rather plain green, narrow foliage growing low to the ground. In late spring flowering stems shoot up, developing and opening tubular flowers, each bloom about 2 inches long. Wild specimens bloom primarily in shades of lavender, white and pink; however selection and breeding now bring dark reds and deep purple selections to the nursery shelves.
In nature, penstemons are found growing in dry woods, areas with scrubby growth or seasonally dry/damp grassy spots; all of that to say, soil drainage is important for healthy plants. Ordinary garden soil with weekly water is the key to a happy Penstemon. Wet roots are a sentence of death once cold temperatures set in, so plan and plant accordingly.
As with most perennials, stems should be trimmed back after bloom. Plants allowed to mature seed may have a harder time sustaining themselves through the hottest days of summer. How then can a thrifty gardener enjoy this easy plant? One can start seed in February or propagate cuttings now.
September is an ideal time to transplant established plants into the garden and to take cuttings to increase your plantings or share with friends. To propagate established plants, choose healthy side branches that have not flowered and snip the stem below a joint about 4 inches below the tip. Gently strip off the lower leaves, bury one-third of the stem in a small pot filled with potting soil. Tamp the soil around the stem and water thoroughly. Place the pot in a bright but shady place for 2-3 weeks; a cold frame is ideal or one can imitate a miniature greenhouse using a clear plastic cover or 2-liter soda bottle with the bottom removed.
After the prescribed time, open the rooting plants to air, but be sure to protect from harsh winter cold. In spring, after frost has past, the cuttings will be ready to transplant in the garden.
Pollinated by butterflies and hummingbirds, penstemons make a fine addition to any garden. Look for the native varieties P. grandiflorus (light purple), P. digitalis (white) or P. ‘Huskers Red’ that has wine-red foliage. A relatively new “family” of Penstemon – Prairie Dusk, Prairie Twilight and Prairie Fire from Nebraskan breeder Dr. Dale Lindgren are also right at home in Stillwater gardens.
LeeAnn Barton has worked with nurseries for more than 20 years. She digs in the dirt in Stillwater. Direct any questions to her, especially about tree selections, by emailing email@example.com.