Hardy Perennials

Helenium hoopesii is considered by some to be the most valuable of the species. It blooms with bright golden yellow disk florets that each form a kind of rounded knob that transforms the flower from your typical two-dimensional daisy into something much more interesting and sculptural.

Perennial sunflowers typically don’t grow quite as tall and large as their annual friends. However Helianthus maximiliani is a wonderful exception. It grows slowly through the summer months as a group of short stems, until late summer when the stems bolt and the flowers head for the sky.

Most gardeners are familiar with the annual sunflower, however, it is the perennial varieties that coexist most happily with other garden plants. Helianthus mollis is a lovely perennial with butter-yellow flowers. It grows 120cm tall and requires little more attention than an annual cutting to the ground.

From the Tian Shan Mountains of northern China comes this tough little subshrub that is among the finest expressions of silver foliage to be found. Helichrysum thianshanicum is a superb silver leaved evergreen, subshrub that forms a tight mound of eye-catching silver foliage.

Heliopsis ‘Summer Nights' is a special selection made by Dale Hendricks of North Creek Nurseries, USA. Introduced in 2004 it produces a profusion of single blooms in early to mid-summer, with rich, deep golden-yellow petals and deep mahogany centres. The foliage is red-tinted and the stems are tinted dark burgundy.

Herniaria glabra is a relatively unknown perennial that deserves to be used more often in our gardens. The nursery industry calls it ‘Green Carpet’ and well they should. This lovely bright green creeper spreads effortlessly in all directions. An excellent choice for between flagstones or as a lawn substitute.

Hosta are grown predominantly for their outstanding foliage, from leaves as small as a teaspoon up to those larger than a dinner plate, colours range from deep blues to silvers, darkest shiny greens to bright yellows, from a single solid hue to the myriad of variegations the choice is almost overwhelming.

Hyssopus officinalis 'Alba' is a much less well known variety of hyssop. Also known as 'White Hyssop' the plants sport bright white flowers from July to October. Widely used as a 'taste enhancing' herb or wildlife plant, the plants are a dark, vibrant green with a spiky, upright habit and narrow tongue-like leaves which have a peppery scent when stroked.

Iris bulleyana is a classic species Iris from western China. It belongs to a small group of oriental species which are entirely hardy and are of great value to the gardener. The plants are successful in any moist garden soil. Flowering from June to July, the blooms with mid purple flowers and dark purple veins.

Yellow Flag Iris is a common and widespread native plant in Britain. This good-looking plant is a wetland plant that is especially showy in bloom and has been transplanted into well-watered gardens all over the world.

Iris versicolor is one of the few species in garden cultivation. Although happiest at the waterside the plants will also perform well under average to moist border conditions. Flowering from May through to July, each stalk produces up to five violet-blue flowers with ruffled petals and bold purple veining.

'Kermesina' is an attractive and popular cultivar of Iris versicolor. Flowering from May through to July with claret-purple flowers with ruffled petals and bold purple veining. It may be grown in shallow standing water or moist shoreline soils and suitable to be grown in constantly moist humusy soils of a border.

Knautia arvensis is an attractive native perennial herb of well drained grassland. It can be found throughout Europe in meadows, rough pasture, hedgerows and verges. Though it is by nature a perennial, it will flower and produce seed the first year if grown as an annual, either autumn or spring sown.

Knautia macedonica has been hugely fashionable for years and is likely to remain so for many more. This lovely and versatile perennial blooms from late spring to autumn with dark-crimson, richly glamorous pompoms. Established plants produce literally hundreds of blooms in one season.

'Melton Pastels' is a great border plant, densely flowering plant with strong stalks of pin cushion flowers in shades of shades of pink, cherry red, mauve and purple. The tall stems make excellent cut flowers and are good for the middle of the border, giving a succession of blooms through till autumn.

The Kniphofia hybrids have extended both the flower colour and height range. The usual fiery reds and oranges work particularly well in a planting scheme based on 'hot' colours - use them to light up sultry August borders. The cooler yellow, cream, ivory and sometimes green flowers is more restful.

Lavendula angustifolia is an excellent plant for low informal hedging and as a specimen evergreen for borders and formal gardens. Flowering generally begins from mid to late June to early July. The flowers have a rich sweet scent and are highly attractive to bees and other beneficial insects.

Munstead Lavender is a fragrant robust English lavender that, due to its short size and tightly held blooms, makes a great hedge. It flowers profusely in the spring, after which a good pruning will provide an attractive grey bush with highly aromatic leaves.