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July's Plant of the month

What looks like a small foxglove but has staying power all summer? What comes in a range of colours – white, pink, red, white, blue, purple…? Pretty penstemons, that’s what

Penstemon 'Alice Hindley'Penstemons are brilliant performers in summer borders year after year. From a garden point of view, there are plenty of cultivars that have been developed that sit beautifully among other plants. Penstemon ‘Alice Hindley’ (left) has pale lilac-blue flowers which are white inside - it’s so pretty and matches lots of colour schemes. In fact, it’s so good it has the RHS Award of Garden Merit (AGM) and grows in the AGM Borders, just off the Mixed Borders.
If you’d prefer a drop of wine-red in your display, Penstemon ‘George Home’ AGM could be the ticket. This also has a white throat, and shows itself off on the AGM Borders nestled alongside pink and blue geraniums.

Penstemon 'Port Wine'Nicer than they sound...

Nearby, Penstemon ‘Sour Grapes’ AGM is much more purple than 'George Home' and has a stripy white throat. ‘Blackbird’ and ‘Port Wine’ (right) put on their show in the half-hardy borders beside the Canal this summer, blending with salvias and osteospermums.

Penstemons are so versatile they have a place anywhere; most of these varieties reach around 60-75cm (24-30in), and if you deadhead them they’ll keep on flowering for ages. Some will survive the winter in their positions, but they’re pretty simple to propagate too – every gardener’s dream.

Useful links

  • Why not come along to the Trials Field at RHS Garden Wisley to see our penstemon trial. We have nearly 100 cultivars on display and they're looking spectacular at the moment!

  • Get RHS advice on growing penstemons

Get involved

The Royal Horticultural Society is the UK’s leading gardening charity. We aim to enrich everyone’s life through plants, and make the UK a greener and more beautiful place.