UK Edition
10 of the best penstemons to plant now for late summer colour
Penstemons rank among the most valuable of late-summer flowering plants.
Their elegant spires of tubular, foxglove-like flowers in tones of pink, red, white, blue and purple are perfect for adding height and colour to a well-drained, sunny border.
Used by indigenous Americans as a toothache remedy, penstemons were popular with the Victorians before falling out of fashion. Now a resurgence in pastel plantings, not to mention their excellent garden value - flowering for more than four months and until the first frost – means penstemons are back in vogue.
Young plants are best planted in spring so they establish a strong root system over the summer. In a sunny or partially shaded spot, they will grow to their full potential within two to five years. They are easily propagated, attract masses of bees and other pollinators and resist many popular garden pests like slugs and rabbits. What’s not to love?
The Royal Horticultural Society (RHS) has trialled more than 100 varieties at RHS Garden Wisley – including border, dwarf and mat-forming penstemons. Here are ten that have been awarded the coveted Award of Garden Merit (AGM).
1. ‘Hewell Pink Bedder’
Flowering over a particularly long period, this clump-forming penstemon boasts bright, reddish-pink flowers with a deep red streaked white throat and silvery grey-green foliage. One of the hardier varieties.
2. Penstemon ‘George Home’
This striking, very free-flowering variety, with dark green contrasting leaves, grows to 70cm and flowers from June to August.
3. Penstemon ‘Pensham Tiger Belle Coral’ (Pensham Series)
Features particularly attractive deep-purplish-red throat markings that contrast with the pale green stems. Grows to 90cm and maintains an upright, uniform habit.
4. Penstemon ‘Evelyn’
Compact and bushy, ‘Evelyn’ has damson-pink flowers that grow up to 1in long. It holds its flowers well between mid-summer and autumn and also features purple-tinged stems.
5. Penstemon ‘Pensham Just Jayne’ (Pensham Series)
Consistently floriferous from mid-summer to autumn, this is a good late-season cultivar with striking pink-magenta flowers and olive-green leaves.
6. Penstemon ‘Rich Ruby’
Steady-flowering throughout the summer, there’s a velvety texture to the rich red flowers that spring from upright, clean foliage with reddish stems.
7. Penstemon ‘Shoenholzeri’
With a lax habit, ‘Schoenholzen’ is perfect for more naturalistic planting schemes. Vibrant red-pink flowers from mid-summer to autumn contrast well with the pale green foliage. It is also frost-hardy.
8. Penstemon ‘Sour Grapes’
The flowers of ‘Sour Grapes’ have an iridescent quality, blending purple and blue shades with a whitish throat.
9. Penstemon ‘Hidcote Pink’
A vigorous rose-coloured plant with light green and purple-tinged stems. Vigorous and growing to 90cm, it produces a uniform display.
10. Penstemon pinifolius ‘Wisley Flame’
This selection arose at RHS Garden Wisley as a chance seedling of Penstemon pinifolius but it has greater vigour and a richer flower colour, that ranges from bright orange to red. Grows to 60cm wide.
For more information about penstemons, to download the RHS Grower Guide or learn more about the Award of Garden Merit, visit rhs.org.uk.