As summer draws to a close and the vibrant rush of colour begins to fade, certain plants step forward to keep our gardens alive with beauty. Among the most valuable of these are Sedums (Ice Plants) and Penstemons, two perennials that shine in late summer and autumn gardens.

These reliable plants don’t just extend the season of colour, they also attract bees and butterflies, provide structure, and demand little care in return. Let’s explore why Sedum spectabile and Penstemons are must-have perennials, how to grow and care for them, and how they can be used to create striking borders.

Sedum spectabile - The Ice Plant of Autumn

If there is one perennial that defines September, it has to be Sedum spectabile, also known as the Ice Plant.

Why Grow Sedum spectabile?

Grows to about 50cm in height.

Long-lasting blooms, from pale pink in July to deep, rich pink in September.

Varieties such as Sedum ‘Autumn Joy’ are garden classics, loved for their reliability.

For me, Sedums are the definition of a “no trouble” plant. They thrive on neglect, need little fuss, and still deliver colour and pollinator interest well into autumn.

 

Favourite Sedum Varieties

Sedum ‘Autumn Joy’  probably the most popular, with masses of pink flowers ageing to bronze.

Sedum ‘Jose Aubergine’ a personal favourite, combining dark purple foliage with cerise-pink blooms that fade to mahogany.

Both varieties are hardy, structural, and perfect for mixed borders.

 

Care Tips for Sedums

The only fault you might find with Sedums is their tendency to flop under the weight of their own foliage and flowers. Personally, I don’t mind if they sprawl across the soil, staking them feels too much like “cotton wool treatment”.

As autumn frosts arrive, Sedums collapse into brown, sodden clumps. But don’t worry,  they’re just retreating underground, ready to reappear fresh in spring.

Lift and divide clumps in mid-November, after they’ve died back. This not only produces more plants for free but also rejuvenates older clumps.

 

Penstemons - Colourful but Temperamental

If Sedums are the reliable workhorses of the autumn border, Penstemons are the divas, temperamental, yet worth every ounce of effort.

Why Grow Penstemons?

Flower continuously from July until the first frosts.

Available in a wide colour range: pink, red, white, purple, blue, even yellow.

Semi-evergreen, offering year-round presence in the border.

My favourite variety is Penstemon ‘Sour Grapes’, with its striking steel-blue flowers. Few perennials provide such rich, tubular blooms so late in the season.

Caring for Penstemons

Penstemons can be a little tricky. Out of flower, they can appear straggly, and it takes restraint not to cut them back immediately. But timing is critical:

Do not cut back in autumn. Cutting too early will almost certainly kill them.

Best time to prune is mid-to-late March, as temperatures rise and new growth emerges.

Deadheading prolongs flowering well into autumn.

Even with correct care, Penstemons are relatively short-lived (five to six years on average). Still, their sheer beauty makes them indispensable.

Propagating Penstemons from Cuttings

Fortunately, Penstemons are easy to replace. Between July and September, take cuttings of fresh growth to ensure a steady supply of new plants.

How to take Penstemon cuttings:

·         Cut 10cm of the current year’s growth just below a node.

·         Remove the flower buds and terminal shoot.

·         Keep one pair of leaves at the top.

·         Dip in rooting powder and insert into compost.

·         Keep indoors until rooted, then plant out the following spring.

·         This simple process makes Penstemons far less risky to grow — and ensures you always have spares.

 

Bee-Friendly Late Summer Flowers

Both Sedums and Penstemons are beloved by bees, butterflies, and other pollinators. In fact, it’s rare to see a Sedum in full bloom without several pollinators feeding at once. Their nectar is rich, reliable, and perfectly timed for when many other flowers are fading.

If you’re looking to make your garden more wildlife-friendly, Sedums are an easy win — low maintenance, structural, and excellent for pollinators in late summer and autumn.

 

Planting Ideas and Combinations

Sedums pair beautifully with ornamental grasses like Stipa tenuissima or Miscanthus, which soften their upright clusters of blooms.

Penstemons work well in cottage garden borders, alongside Geraniums, Phlox, and Salvias.

Combine Sedum ‘Jose Aubergine’ with silver-foliaged plants like Artemisia for a striking contrast.

These pairings extend the season of interest, keep borders looking full, and help disguise straggly foliage.

Why Sedums and Penstemons Belong in Every Garden

When planning your late summer and autumn garden, think beyond the typical bedding plants. Sedums and Penstemons provide structure, colour, and nectar at a time of year when gardens can begin to look tired.

Sedums (Ice Plants): hardy, easy, and long-lived.

Penstemons: colourful, less reliable, but worth every bloom.

Together, they ensure your garden is alive with colour, pollinators, and interest right up to the frosts. And while Sedums thrive on neglect, Penstemons reward you for that extra bit of care, a combination that balances reliability with indulgence.

So, if you’re looking for the best perennials for late summer colour, it’s hard to beat Sedum spectabile and the ever-alluring Penstemon.