Penstemons are ideal for dry conditions with poor soil, but their sophistication doesn't stop there. They have beauty, long-lasting blooms, come in a variety of colors, are easy to care for, and they attract hummingbirds and butterflies. Does that make them almost perfect for Mohave County?
The penstemon's common name is beardtongue because of the often-hairy stamen that stands out of the tubular flower. Native Americans used penstemon roots to treat toothaches; however, I do not suggest you try that.
Penstemons first gained horticultural attention in 1748. By the 19th century, British and French horticulturists were busy creating hundreds of hybrids. By the 20th century, Americans were starting to produce different types too. In 1946, the Penstemon Society was formed. There are more than 250 species of penstemon.
If you are a little lax in caring for your flower beds, then penstemons are the flower for you. They love eight hours of direct sunlight and will even tolerate 10 to 12 hours. Well-drained soil is a must because they love dry soil. This is one of the very few times you will hear me say, "Don't use mulch." Penstemons do not like moist crowns.
Whatever you do, don't pamper them. Fertilize and water sparingly. Penstemons prefer poor, dry soil, and will flop if you fertilize them too much. Most penstemons will bloom for weeks if you deadhead their spent blossoms.
Penstemons are airy plants, so they look best when planted in groups of 12 or more. Another advantage to planting them in groups is they attract hummingbirds and butterflies. With their diversity of both tall and short varieties, they make great border plants
The tallest of the penstemons grow about 3 feet tall and 2 feet wide and love our hot, dry climate. They can put on a spectacular floral display from summer into fall.
The Rocky Mountain (Penstemon strictus) have gorgeous lavender flowers that last for months, and this variety lives for many years, unlike others that survive for just a few years. Two other tall members of this family are: the Desert Penstemon (Penstemon pseudospectabilis) which grows about 3 feet tall and 18 inches wide. It blooms most of the summer with spikes of hot pink flowers; and the Russian Sage (Perovskia blue spire) which boast lavender-blue flowers.
For a shorter contrasting variety, try Penstemon Red Rock which grows 18 inches tall and 15 inches wide, with glossy foliage and rose-pink flowers, or Sedum (Sedum Vera Jameson) which displays pink flowers in the late summer with burgundy foliage. To complete your contrasting heights, add one of the shortest members of the family, Creeping Baby's Breath (Gypsophila repens), which grow only 4 to 6 inches tall and 15 to 18 inches wide, displaying tiny white flowers. I have only named a few of the many varieties that will grow well here.
Penstemons are perennials, but after three or fours years when their performance starts to decline, you may want to replace them. You can start new plants from stem cuttings taken in spring or summer, or start seeds. In the fall, fill a pot with potting soil or seed-starting mix, smooth over, tap down and water in well. Sow the seeds thinly over the surface of the mix. Press them gently into the mix with the palm of your hand. Cover the seeds with horticulture sand or vermiculate. Label the pot. Place the pot outside on a level surface so that it is exposed to all weathers, including frost.
The fluctuating temperatures will help to break down the outer protective coating on the seed. This is referred to as natural stratification. Do not worry if your pot becomes covered with snow. This method works well if you live where for at least three weeks during a three-month period of winter the temperature reaches 32 degrees or below.
Penstemon seeds need chill hours to germinate, so if you're outdoor temperatures do not reach at least 32 degrees, you could always put the pots in the refrigerator. Knowing most of us do not have an extra refrigerator just to germinate seeds, here is an alternative referred to as artificial stratification. Place the seeds in a paper napkin then fold it and moisten with water. Not sopping wet, just moist. Place the napkin in a Ziploc bag, label it, and place it in the refrigerator. After four to six weeks, remove the seeds from the refrigerator, put the paper napkin with the seeds on it in a pot filled with potting soil. Cover with a light layer of potting soil and put outdoors.
Like all seedlings and young plants, keep moist until they mature. Don't worry about the paper napkin, it will decompose. Another method to scarify: mix seeds with moist peat moss or seed-starting medium in a Ziploc bag. Close the bag and place it in the refrigerator for four to six weeks. Then sow the mixture as you would normal seeds.
This method, however, does not work well with very tiny seeds, as you cannot tell how thickly you have them planted. Seedlings may bloom the first year. Many penstemons produce an army of seeds and rejuvenate themselves each year. Some seeds require light to become seedlings, others do not; some need to receive chill hours (temperature below 45 degrees) before two little leaves pop out of the ground, others do not. As a result, penstemon seedlings appear under a wide range of conditions in both late winter and early summer.
One last added benefit to the penstemon is they make a great cut flower. With their long stems and intricate flowers, they will last three to five days in a vase, bringing their outdoor beauty indoors.
Kingman Area Master Gardeners will present a Preparing for Spring workshop from 9 a.m. to 1 p.m. Saturday, Oct. 23, in Hualapai Mountain Medical Center Conference Rooms A & B. The hospital is located at 3401 Santa Rosa Drive. There is no charge for this public workshop. Topics to be covered include Seed Selection, Soil Preparation, Dividing Bulbs and Tubers, Perennial Care and Controlling Insects. Seating is limited. Call (928) 753-3788 to reserve a seat.