10 award-winning trailing alpines

Back in the days when alpines and rock plants were grown in rock gardens, trailing types were invaluable in hugging the rocks to hide their bulk and cascading down to create sheets of colour. Although times have changed and we now prefer raised beds, gravel gardens and large containers for our alpines, trailing plants are just as valuable. They can tumble over the edge of raised beds, creep across gravel

Mulch is a layer of material, at least 5cm (2in) thick, applied to the soil surface in late autumn to late winter (Nov-Feb). It is used to provide frost protection, improve plant growth by adding nutrients or increasing organic matter content, reducing water loss from the soil, for decorative purposes and suppressing weeds. Examples include well-rotted garden compost and manure, chipped bark, gravel, grit and slate chippings.

A classy classic

White flowers of up to 2cm in width bloom in late spring

Arabis is a classic May-flowering alpine that anyone can grow. This double-flowered form, Arabis alpina subsp. caucasica ‘Flore Pleno’ extends the flowering period compared to single forms, and adds a little class to the act. Spreading about three times as wide and high, the neat, grey-green, evergreen leaves make an ideal background for the pure white flowers and an attractive carpet for the remainder of the year. Height can reach 20cm (8in). Hardiness rating: H5.

Aubrieta upgraded

Each flower is delicate and a rich violet-blue colour 

Another special form of an old favourite. The vivid flower colour sets Aubrieta ‘Doctor Mules’ above the more widely seen forms whose colouring is often rather pale and thin. The evergreen foliage spreads happily over sunny banks, trails from cracks in walls, or over the edge of a raised bed, and can spread to 50cm (19in). It is densely covered in flowers during April. Height can reach 10cm (4in). RHS hardiness rating: H5.

Bushy and billowing

Greyish-green leaves with plentiful, small, bright yellow flowers bloom

A slightly bushy trailer, the clouds of yellow flowers that cover Aurinia saxatilis in May are unusual in the richness of their mustard-tinted colouring. Billowing over the edges of raised beds, or even as a specimen in a terracotta pot, the hairy grey-green leaves make the ideal background. This is a resilient little plant, more like a twiggy little shrub than a traditional alpine. Height can reach 20cm (8in). RHS hardiness rating: H5.

Lovely on walls

Starry, light violet-blue flowers sit in contrast with the greenery

Campanula poscharskyana ‘Stella’ is an easy, vigorous – sometimes too vigorous – alpine, especially suited to cracks in walls. In fact, plant it at the edge of a raised bed and before long the shoots will be bursting through the wall lower down. The long trails of bright, violet-blue summer flowers are charming and open over many weeks. Height can reach 15cm (6in). RHS hardiness rating: H5.

Rare British native

An evergreen perennial with fragrant petals

Dianthus gratianopolitanus is a rare British native, found only in the Cheddar Gorge, Somerset. It is a lovely evergreen, mat-forming

Perennials are plants that live for multiple years. They come in all shapes and sizes and fill our gardens with colourful flowers and ornamental foliage. Many are hardy and can survive outdoors all year round, while less hardy types need protection over winter. The term herbaceous perennial is used to describe long-lived plants without a permanent woody structure (they die back to ground level each autumn), distinguishing them from trees, shrubs and sub-shrubs.

Vertical sheets of flowers

Slender stems holding very pale pink flowers

Gypsophila ‘Rosenschleier’, also known as baby's breath 'Rosenschleier', is a compact, semi-evergreen perennial with slender stems and narrow, grey-green leaves. Large, open panicles of pale pink

A type of flower that has extra petals, often having a fuller appearance. Plants with double flowers are often considered more ornamental and showy than those with single flowers, though they are generally not as good for wildlife, having little or no pollen. Some plants naturally produce double flowers, while others may be bred for this trait. Examples of plants with double flowers include roses, sunflowers, dahlias, and zinnias.

Bright sunny flowers

Stems crowded with small green leaves hold bright yellow flowers

Another of this selection featuring greyish-green foliage, Hypericum olympicum is a twiggy little

Deciduous refers to plants (mainly trees and shrubs) that lose their leaves seasonally, usually during autumn. This is a natural process triggered by the season's shorter days and lower temperatures and allows plants to conserve energy during the winter months.

Blue beauty

An evergreen shrub with vivid blue flowers

In May and June (and often earlier), the sparkling, deep blue, five-pointed flowers of Lithodora diffusa ‘Heavenly Blue’ bring a colour to alpine plantings that is not often seen. This widely spreading, mat-forming, evergreen shrub has dark green, slightly bristly foliage. Best grown in pockets of humus-rich, acid soil, it is also well suited for growing as a specimen in a container or trough. Height can reach 15cm (6in). RHS hardiness rating: H5.

A star of autumn 

The small pale pink flowers deepen to crimson with age

Persicaria affinis ‘Superba’ is an invaluable late-flowering trailer from August to October, bringing colour to alpine plantings at a time of year when other alpines are long finished. An interlocking mat of reddish stems carries tightly packed, evergreen leaves, which develop bronze-brown tints in autumn. The 7cm (3in) long, upright, cylindrical spikes of small flowers open pale pink and become increasingly dark as the weeks pass. Height can reach 20cm (8in). RHS hardiness rating: H5.

Phlox is essential

Deep crimson flowers, 1.5cm in width, bloom in late spring and early summer

The two creeping alpine Phlox species. Phlox douglasii and Phlox subulata, should be at the top of the list of trailing alpines and Phlox douglasii ‘Red Admiral’ serves as a fine representative of the six cultivars awarded an AGM. Phlox douglasii is the more compact of the two, spreading to 30-40cm (12-16in), the fresh green, evergreen foliage hidden in spring by a mass of rounded flowers, in this case in deep reddish-pink. Height can reach 10cm (4in). RHS hardiness rating: H5.