A Wildflower for the Rock Garden

Almost anywhere from the east coast to the west coast Penstemons can be found in the wild but they are not all the same species and they don’t always look the same. They can also be found in most any habitat from moist to arid but most are found in sunny locations such as meadows or dry mountain slopes.

Most Penstemon species have tubular flowers with five lobed margins. The name Pens (penta) and stemon (stamen) comes from the five stamen which bear anthers filled with pollen and all species of Penstemons have this characteristic. Another name for Penstemons is beard tongue because at the opening to the tubular flowers where the stamen protrude are some hairs. However, tubular flowers and five stamen are about the only visible characteristics found in all Penstemon species.

If you don’t like the color of one Penstemon species try another one since this genus has flowers ranging from hot pink to brilliant red and from yellow to purple and blue. They also come in a range of sizes from low mat forming or mound forming plants like Pineleaf Penstemon (Penstemon pinifolius) to large stocks suitable for floral arranging like Palmer’s Penstemon (Penstemon palmeri).

The less desirable characteristics of Penstemons is they tend to only bloom in late spring or early summer and they are short lived perennials and must be replaced every few years. A few, like Palmer’s Penstemon will rebloom during the growing season if the flowering stocks are cut before they can set seed and they make lovely scented cut flowers for floral arrangements.

PurchasingPenstemons

A few Penstemons like Penstemon pinifolius have made it into the popular nursery trade but most will only be found in nurseries specializing in native plants. Those Penstemon species not commonly found in the nurseries will need to be started from seed. Seed for Penstemons is acquired from seed companies specializing in native seed. Another way is to join a native plant society in your area with gardeners who raise Penstemons and save the seed.

Growing Penstemons

Raising Penstemons from seed can be tricky depending on the species. Species from wetter climates tend to germinate more easily than ones native to dry climates where moisture availability is more erratic. The latter may require periods of cold stratification before they will germinate. To achieve cold stratification it may be necessary to plant the seed in the fall or place in the refrigerator with moist seed starting media such as moist vermiculite or soil less mix.

Whether you purchase plants or start them from seed, Penstemons like good drainage so find an area in your rock garden or perennial bed that has good drainage before you either scatter seed or place a Penstemon plant. If you wish to have them go to seed either plan on collecting the seed before if falls from the seed pods or plan to have bare soil at the base of the plant because Penstemons don’t germinate well in mulch.

Maintaining Penstemons

Penstemons don’t require a lot of maintenance but they also are not a season long attraction in your garden. Some have nice foliage to look at after the flowers have faded but the flower color will likely be gone after the blooms have faded and the seed pods have formed. Flowering may be extended on some species like Penstemon palmeri if the blooms are cut before seed set. However, no pruning of this perennial is necessary.

Fertilizing is also not necessary in most cases because these flowers are native and will form associations with soil organisms that will help these plants acquire nourishment from the soil.

Depending on the species and how well your garden imitates the Penstemon’s native environment, they may only need once or twice a week watering. However, be sure they have good drainage because Penstemons tend to die if their roots remain constantly wet.

Few pests bother Penstemons so spraying them for insects isn’t necessary and can be undesirable if you want to watch the hummingbirds that are attracted to flowers.