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10 award-winning (AGM) tough, attractive perennials

Perennial plants combine effortless beauty with year-round resilience, offering reliable colour and structure in even the most challenging conditions

Planted once and given space to establish, these resilient

perennials rise to the challenges of the year, offering dependable displays as the seasons shift. Recognised for their strength and ornamental value, they pair lasting beauty with exceptional staying power. With the RHS Award of Garden Merit (AGM) and a hardiness rating of H6 or H7, they withstand the coldest winters and return each spring with renewed vigour, making them ideal for both new gardeners and established borders.

Lily of the valley

Delicious scent and dainty looks belie the lily-of-the-valley’s tough nature

Lily-of-the-valley (Convallaria majalis) is a rare British

native whose perfume and quiet beauty are captivating. In shady spots the roots can sometimes spread strongly, with the dark foliage making effective ground cover and the ideal background for the arches of nodding white bells. It’s always worth growing for those delightful flowers and the red berries that follow. 20cm (8in).

Golden discs

The horizontal flowerheads of Achillea ‘Coronation Gold’ provide pit-stops for bees and other pollinating insects

Yarrow – Achillea ‘Coronation Gold’ has vertical stems and flat horizontal flowerheads which bring a delightful combination of flower and foliage colour. The greyish feathery leaves form an attractive cluster of foliage when they first emerge, while the heads of tiny flowers are bright yellow. Plant in sun in any reasonable well-drained soil. 90cm (3ft).

Late summer blue

Not many late-summer perennials produce blue flowers like Aconitum ‘Arendsii’

Monkshood – Aconitum carmichaelii ‘Arendsii’ – is invaluable for bringing its rich lavender-blue colouring to the autumn garden which is more often filled with orange and rusty shades. The leathery, dark green leaves set off the short spikes of flowers beautifully. 1.2m (4ft).

Top tip: Appreciate with eyes only

All parts of this plant are poisonous; wear gloves when handling.

Hardy succulent

Choose this joyful sedum for cool-coloured leaves and pink flowerheads in late summer and autumn

‘Autumn Joy’ sedum (Hylotelephium ‘Herbstfreude’) is surprisingly frost hardy. It’s not for nothing that sedums of this type are called ice plants. Broad, deep pink flowerheads open in August and September and turn brown as they remain on the plant for autumn and winter interest. Provide support for your plants if your garden soil is on the fertile side, as they may grow lush and flop ever when in flower. 50cm (20in).

Dramatic coneflowers

Helenium ‘Rubinzwerg’ is attractive to pollinating insects and makes a strong impact in late summer

Helenium ‘Rubinzwerg’ is a compact, bushy

perennial valued for its striking dark red flowers that age to warm orange, with prominent brown centers. Blooming from July to September, it provides essential nectar and pollen for bees and other pollinators. Hardy and reliable in a wide range of climates, its upright stems and narrow green foliage make it a standout in borders or pollinator-friendly gardens. Height 1m (3ft 4in). Hardiness rating H7.

Textured foliage

Hosta sieboldiana var. elegans enjoys partial light and dappled shade to form large, architectural leaves

Hosta sieboldiana var. elegans is an old and dramatic favourite with large, blue-green, corrugated leaves and short spikes of white flowers in early summer. Plants develop into striking clumps, making impressive specimens in light or partial shade. Late frost may damage new shoots, but by summer you’d never know. Height 80cm (2½ft). Hardiness rating H7.

Cottage garden favourite

This old cottage garden favourite does best grown in dappled shade

Bleeding heart – Lamprocapnos spectabilisis better known by its old name of Dicentra spectabilis. This is one of the most elegant of perennials in the arching growth of its succulent stems – and one of the most intriguing in the colour and structure of its pink and white flowers. It may be damaged by late frosts but it always recovers. The lovely pure white flowered form, Lamprocapnos spectabilis ‘Alba’ also has an AGM. Height 90cm (3ft). Hardiness rating H6.

Multi-season interest

Jerusalem sage bears pretty yellow flowers in summer
Structural seedheads give months of interest in autumn and winter

Perfect for hot, dry gardens, Jerusalem sage (Phlomis russeliana) is an unexpectedly hardy perennial. In spring you may think it has succumbed to winter cold, but it is noted for its late emergence. The bold, slightly felted lower leaves support upright stems carrying clusters long lasting yellow summer flowers; its seedheads then make an interesting feature in autumn and winter. Height 90cm (3ft). Hardiness rating H6.

Sunny daisies

The intense brightness of rudbeckiaGoldsturm’ catches the eye immediately 

Rudbeckia fulgida var. sullivantii ‘Goldsturm’ is one of the brightest of summer perennials. The deep yellow ray petals strike out boldly around the chocolate brown central cone, each flower held on an upright stem, which supports itself well if the soil is not too rich. With a long flowering season from July to October, this is a colourful sun lover usually comes true from seed. Height 80cm (2½ft). Hardiness rating H6.

Lady’s mantle

Soften path edges with lady’s mantle Alchemilla mollis for an authentic cottage-garden look

Lady’s mantle (Alchemilla mollis) is both valuable and exceptionally hardy. Its chartreuse flowers blend happily with most other shades, while its soft lobed foliage is always appealing, especially when holding dewdrops. Cut the flowers off as they fade to prevent

seedlings taking over. Height 45cm (18in). Hardiness rating H7.

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