Nigel Colborn - Plant Solutions

Height and spread:Variable to 1m × 45cm (3ft 3in × 1ft 6in)

Companion plants:Bright companions for red salvias or among cooler blues and mauves of autumn-flowering asters. Also useful for late bedding schemes.

Biennials for scent

Dianthus barbatus

Sweet William Hardy annual or short-lived perennial

Member of the pink family, its branching stems furnished with broad or narrow dark green or purple-bronze leaves, are topped with clusters of flowers. The sepals are narrow and extended like little green beards. The fragrant blooms are maroon, red, pink, white or bicoloured and last for several weeks.

Soil preference:Any free-draining

Aspect:Sun

Season of interest:Early to midsummer

Height and spread:To 60cm × 45cm (2ft × 1ft 6in)

Companion plants:Great favourite for cottage planting and good company for annuals such as larkspurs and cornflowers, or to grow at the feet of climbing or bush roses. Also prized as a cut flower.

Viola x williamsii ‘Bedding Supreme’

Miniature pansy Hardy biennials or short-lived perennials

Seed-raised selections of small-flowered pansies or violas with honey-scented, five-petalled flowers produced above lobed leaves. short-lived as perennials, but can be kept in flower for months by regular deadheading. Good series: ‘Bedding Supreme’ comes in a broad colour mix, ‘Singing in the Blues’ in shades of purple, violet and blue.

Soil preference:Any free-draining but not too dry

Aspect:Sun, part shade

Season of interest:Winter, spring, summer

Height and spread:20cm × 30cm (8in × 12in)

Companion plants:Like all pansies and violas, these plants fit anywhere with anything. Lovely in a cottage border, seeding among pinks, antirrhinums or in semi-shade with small dicentras or between polyanthus.

Matthiola incana

Stock, Brompton Stock Biennial

Glaucous, slightly downy, grey-green foliage which produces multiple short stems, or long single stems bearing highly fragrant single or double blooms in white or shades of violet, mauve or pink. Cutting varieties include Ten Week stocks, but the wild species is attractive for cottage garden use. Excellent bee plant.

Soil preference:Any free-draining

Aspect:Sun

Season of interest:Summer.

Height and spread:Variable to 1m × 20cm (Variable to 3ft 3in × 10in)

Companion plants:Once popular for overwintered bedding, Brompton Stocks are more frequently used to dot among early summer mixed borders, preludes to pinks or border carnations, or to grow among bush roses.

Biennials with distinctive foliage

Onopordon nervosum

Scottish Thistle Hardy biennial

R. Coates

Metallic, silvery-grey leaves form dramatic rosettes in autumn and thick, winged, branched stems rear up during spring and summer, creating tree-like structures decorated in summer with purplish red thistle flowers. Viciously armed in all its parts. A prolific self-seeder.

Soil preference:Any free-draining

Aspect:Full sun

Season of interest:All year, mainly summer

Height and spread:Up to 3m × 1.5m (10ft 9in × 4ft 6in)

Companion plants:Their architectural shape make these ideal plants for providing dramatic summer statements, particularly among soft outline perennials such as cranesbills. Also excellent in sparse gravel planting.

Lychnis coronaria

Rose Campion Hardy biennial

Loose rosettes of oval, felty, grey leaves develop in the first year. Branched, erect stems develop during the second spring and in summer carry a long succession of bright cerise, disc-shaped flowers. The form ‘Alba’ has white flowers which age to pale pink, whereas the petals of ‘Atrosanguinea’ are blood red.

Soil preference:Well-drained

Aspect:Sun

Season of interest:Summer

Height and spread:1m × 50cm (3ft 3in × 1ft 8in)

Companion plants:A free self-seeder, which is lovely dotted about among the more rigid spikes of lupins or to harmonize with lavenders and Perovskia.

Silybum marianum

Our Lady’s Milk Thistle, Blessed Thistle Hardy biennial

Heather Angel

Dark green, undulating, prickly leaves, each marbled with white streaks, form a loose-knit groundcover during spring. Flower spikes develop in summer producing deep purple thistle flowers, but the value is in the foliage. The name arises from the legend that the Blessed Virgin Mary dripped milk onto the leaves. Watch for slugs and snails.

Soil preference:Any well-drained

Aspect:Sun or part shade

Season of interest:Summer

Height and spread:50cm × 1m (1ft 8in by 3ft 3in)

Companion plants:Valuable for linking spring with summer and lovely among early flowering perennials such as lupins, early poppies and perennial wallflowers.

Other good biennials

Trifolium rubens

Hardy biennial

Heather Angel

A compact, bushy clover with typical three-lobed leaves and, during summer, elongated, slightly furry buds which open to produce tight groups of crimson flowers. An excellent cut flower and extremely bee-friendly. Like all legumes, the plant fixes its own nitrogen from the atmosphere.

Soil preference:Any free-draining

Aspect:Sun or part shade

Season of interest:Summer

Height and spread:45cm × 20cm (18in × 8in)

Companion plants:A plant to blend harmoniously with the annual hare’s foot grass, Lagurus ovatus , whose flowers are similar in shape, but contrast in colour. Also good in a mixed border, to fill gaps between later flowering perennials.

Trifolium incarnatum

Italian Clover, Crimson Clover Annual or biennial plant

A vigorous annual or biennial whose young foliage is vivid emerald green. The three-lobed leaves form a neat mound during autumn followed, in late spring, by a succession of waving stems topped with oblong clover flowers in bright claret red. Not suitable for autumn sowing where winters are hard.

Soil preference:Any free-draining