Long floral scapes lined with cute bell-shaped flowers in red, violet and yellow make beardtongue (Penstemon) easy to mistake for a foxglove. This American perennial is grown for spectacular colour in beds, borders and pots; give it full sun and rather rich, well-drained soil and it flowers from late spring right through to mid-autumn.
| Name | Penstemon |
|---|---|
| Family | Scrophulariaceae |
| Type | Perennial |
| Height | 1 to 4 feet (30 to 120 cm) depending on the variety |
| Exposure | Full sun, part sun |
| Soil | Rather rich and well drained |
| Flowering | Late spring to mid-autumn |
If you purchased your plants in nursery pots, it is best to plant them in the ground in spring, spacing them 12 inches (30 cm) apart and adding “flower plant” soil mix to the garden soil.
Beardtongues are actually well suited to growing in pots for balconies and terraces.
Has your beardtongue patch grown too thick?
Sowing beardtongue is difficult and efforts aren’t always crowned with success.
However, you can also simply let a few flowers go to seed, and some of them will sprout naturally in the spring.
Beardtongue can be multiplied from seed, from cuttings or by moving clumps around, and the three routes differ sharply in timing and in how often they work. Use the table to pick the one that suits the plants you already have.
| Method | When | Success rate | Ready to plant out |
|---|---|---|---|
| Sowing in a nursery | Late winter, under shelter at 65 to 68°F (18 to 20°C) | Difficult, not always successful | The following spring |
| Letting flowers go to seed | Sprouts appear in spring, where the seed fell | Hit and miss, only some seeds sprout | Leave them where they come up |
| Stem cuttings | Summer, from stems bearing no flowers | Usually rather good | The following spring |
| Transplanting or dividing clumps | Spring, after the last frosts | Reliable, and keeps named hybrids true | Straight into its new spot |
Whichever route you take, young plants go into the ground in spring once frosts have passed.
Beardtongue cuttings are prepared in summer and usually lead to rather good results.
Because named beardtongue (Penstemon) hybrids do not come true from seed, they are kept true by vegetative propagation—commonly stem cuttings, but also division or tissue culture—since seedlings vary in their traits.
Caring for beardtongues is easy once they are well settled in. Apart from the occasional watering, you won’t need to care for them at all.
In winter, no need to remove beardtongue leaves: they protect the plant from the cold. What is best is to cover the plant with a thick layer of dead leaves to protect it from freezing.
Beardtongue is hardy to temperatures as low as 23°F (-5°C) and even 5°F (-15°C), depending on the variety.
Native to America, beardtongue is a beautiful perennial that bears long floral scapes with cute bell-shaped flowers. Often compared to foxglove, they are sometimes mistaken one for the other.
Also called penstemon, there are over 250 varieties of beardtongue with as many colors, shapes and sizes.
Dominant colors are red, violet and yellow, and Penstemon barbatus and Penstemon heterophyllus are most common. Many hybrids have been developed to this day.
They are easy to grow, require little care, and the result is guaranteed to make an impact with their spectacular flowers.
You can also cut a couple beardtongue flower stems and place them in a vase, they keep for a long time!
