Top 10 Hardy Plants For Late Summer

Top 10 Hardy Plants For Late Summer

By August, the garden begins to relax as early summer colour fades. Many flowering plants are running out of steam, and green becomes the dominant shade throughout borders.

Top 10 Hardy Plants For Late Summer

By August, the garden begins to relax as early summer colour fades. Many flowering plants are running out of steam, and green becomes the dominant shade throughout borders.

Fading borders are a common complaint, but you needn't say goodbye to summer colour just yet. There are plenty of hardy shrubs and perennials that peak later in the growing season, refreshing planting schemes and extending the season for a few more months.

Read on to learn which hardy plants you can buy online from Thompson & Morgan to breathe life back into late summer borders.


1. Crocosmia

From late spring its upright, strap-like foliage adds height and structure to planting schemes even before the flowers appear! Late summer sees its arching stems tipped with sprays of trumpet-shaped flowers in the brightest shade of yellow, orange and red. Crocosmia 'Lucifer' is one of the best known cultivars. This tall perennial is tough and reliable, and looks great in 'hot' coloured borders with its fiery scarlet blooms.


2. Tulbaghia

I adore this plant! The slender grey-green foliage and soft lilac flowers make an elegant combination. Flowering from midsummer, Tulbaghia gathers momentum, reaching its peak in august. Tulbaghia violacea is the hardiest of the family, overwintering successfully in well drained sheltered spots. This garlic-scented perennial makes an unusual container plant, and forms a wonderful grassy effect in borders


3. Clerodendron

Another plant for a sheltered position - rarely seen in UK gardens but well worth a go! Clerodendron bungei 'Pink Diamond' is a particularly attractive choice with cream and olive-green variegated foliage that turns to fiery red in autumn. Large heads of perfumed flowers appear from late summer, often continuing into October. Curiously, the aromatic foliage tends to have the 'Marmite-effect' - some folk love it and others are repelled by it!

Lobelia cardinalis

4. Lobelia cardinalis

Late summer colour needn't be confined to sunny perennial borders - the scarlet blooms and of Lobelia cardinalis will brighten up pond margins and moist, boggy areas from August to October. Lobelia cardinalis 'Queen Victoria' has contrasting purple-tinted foliage which makes a majestic and exotic looking focal point.

Japanese Anemones

5. Japanese Anemones

Anemone hupehensis and A. x hybrida have long been associated with the ordered style of traditional Japanese gardens, hence their common name of Japanese Anemone. I've always found them to be utterly reliable. The elegant, cupped shaped blooms rise above rounded clumps of handsome foliage, forming large drifts in borders.

Verbena bonariensis

6. Verbena bonariensis

Verbena bonariensis has seen resurgence in popularity in recent years, making it instantly recognisable to many gardeners. The flattened, lavender-purple flowers bring a swaying, airy effect to the back of borders, and seem to glow at dusk and on cloudy days. Blooming from July, this tall perennial reaches its peak in late summer and continues into autumn. A single plant is easily lost in crowded late summer borders so mass plants together in large swathes for the best effect.

Hydrangea paniculata

7. Hydrangea paniculata

Think of Hydrangeas and the mophead macrophylla types tend to come to mind. But Hydrangea paniculata is arguably more refined, with its characteristic conical flower heads that make a showy display in late summer. The vibrant autumn foliage extends its season of interest well into October making this a real showstopper, particularly useful for those cold north facing spots. There are plenty to choose from but Hydrangea paniculata 'Vanille Fraise' is a popular cultivar for its pink flushed blooms. For smaller gardens, choose low growing H. paniculata 'Bobo' which reaches just 90cm (36") tall.


8. Pennisetum

Ornamental grasses create valuable texture in borders, softening hard landscaping, and providing good ground cover too. Pennisetum is an attractive genus, with many different forms and foliage colours. Pennisetum villosum 'Cream Falls' is a favourite for containers and the front of borders with fluffy, late summer flower heads above neat clumps of slender foliage. For a similar effect at the back of the border use the taller species P. alopecuroides.


9. Caryopteris

The compact, rounded habit of Caryopteris makes it useful for the middle of mixed borders, where it associates nicely with grasses and low growing perennials. The glorious blue flowers provide a valuable source of nectar, attracting plenty of pollinating insects to the garden. There's a good range of cultivars to choose from, with some interesting aromatic foliage, from traditional grey leaves to the more vibrant gold-green of Caryopteris x clandonensis 'Hint of Gold'. My personal favourite is Caryopteris x clandonensis 'White Surprise' for its delicate variegation.


10. Sedum

These fleshy-leaved perennials are the masters of drought tolerance, thriving in well drained, hot, sunny borders. Large panicles of tiny flowers pink or white flowers make a showy display at the front of borders, and are a magnet for butterflies. If you like dramatic foliage try one of the darker cultivars such as Sedum telephium 'Purple Emperor'. These hardy perennials are ideal for herbaceous borders and gravel gardens. Sedum ussuriense 'Turkish Delight' makes a particularly nice, low growing form for rockeries.

For everything you need to know about keeping your borders bright and colourful throughout the summer, visit our summer flowers hub page.

Sue Sanderson T&M horticulturalist

Written by: Sue Sanderson

Plants and gardens have always been a big part of my life. I can remember helping my Dad to prick out seedlings, even before I could see over the top of the potting bench. As an adult, I trained at Writtle College where I received my degree, BSc. (Hons) Horticulture. After working in a specialist plantsman's nursery, and later, as a consulting arboriculturalist, I joined Thompson & Morgan in 2008. Initially looking after the grounds and coordinating the plant trials, I now support the web team offering horticultural advice online.

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