Penstemon, bright colors

Red trumpet penstemon flower bloom close up.

Penstemon, also called beardtongues, are beautiful perennials that bloom all summer long.

Penstemon main facts

NamePenstemon
Family – Scrophulariaceae (figwort family)
Type – perennial

Height – 26 to 32 inches (0.6 to 0.8 meters)
Exposure – full sun, part sun
Soil – rather rich and well drained

Flowering – May to October

Easy to grow, here are the best practices to care for your Penstemon and extend their blooming.

Planting and sowing Penstemon

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.

  • Plant at least ten plants in any given bed to produce a remarkable visual impact.
  • Water regularly after planting.

Planting Penstemon in pots

Penstemon thrive particularly in pots or garden boxes.

  • Plant in flower plant soil mix.
  • Water regularly at the beginning and then, especially in summer, only when the substrate surface is dry.
  • Never flood the roots.

Sowing Penstemon

Sowing Penstemon is difficult and efforts aren’t always crowned with success.

  • Sow in a sheltered place, in a nursery at the end of winter in special seedling soil mix.
  • Place seedlings to light at a warm temperature, around 65 to 68°F (18 to 20°C).
  • Sprinkle water over lightly to keep the substrate a bit moist.
  • Transplant into nursery pots after sprouting when sprouts have formed a few leaves.
  • Transplant in the ground in the following spring.

Preparing Penstemon cuttings

To propagate your Penstemon easily, summer cuttings are definitely the best solution. You can even use stems pruned off in spring to prepare cuttings.

  • Snip off cuttings from Penstemon stems that aren’t bearing flowers.
  • Eventually, dip the cuttings in powdered rooting agents (this step isn’t necessary, but it helps).
  • Plant your Penstemon cuttings in cutting soil mix.
  • Keep substrate a little moist, reduce watering in winter.
  • Protect cuttings from freezing in winter but keep them in a well-lit place.
  • Transplant in the ground in the following spring.

Pruning and caring for Penstemon

Pruning and caring for Penstemon is easy. Apart from the occasional watering during summer, you won’t need to care for them at all.

  • To boost flower-bearing, remove wilted flowers regularly (deadheading), since this will stimulate the budding of new blossoms.
  • Water Penstemon in case of high temperatures, preferably in the evening.
  • Mulching the base of your Penstemon helps keep the soil cool and reduces the need to water.

In winter, no need to remove leaves: they protect Penstemon from the cold. What is best is to cover the plant with a thick layer of dead leaves to keep it from freezing.

Penstemon are hardy to temperatures as low as 23°F (-5°C) and even 5°F (-10°C), depending on the variety.

All there is to know about Penstemon

Purple penstemon flower against a background field full of purple penstemon.Native to the vast American plains, Penstemon is a very beautiful perennial that bears large floral scapes with cute bell-shaped flowers at their tip. Often compared to foxglove, they are often mistaken one for the other.

Also called beardtongue, there are over 250 varieties of Penstemon with as many colors, shapes and sizes.

Dominant Penstemon colors are red, violet and yellow.

Interesting Penstemon varieties

  • Penstemon barbatus – cherry-red.
  • Penstemon ‘Evelyn’ – pale pink.
  • Penstemon ‘Garnet’ – raspberry red.
  • Penstemon heterophyllus – lavender blue.
  • Penstemon ‘Hidcote Pink’ – pink
  • Penstemon ‘Midnight’ – purple
  • Penstemon ‘Souvenir d’Adrien Régnier’ – pink
  • Penstemon ‘Snow storm’ – white
  • Penstemon ‘White Bedder’ – white

Smart tip about Penstemon

You can also cut a couple Penstemon flower stems and place them in a vase, they keep for a long time!


Image credits (edits Gaspard Lorthiois):
CC BY 2.0: tdlucas5000