Nigel Colborn - Plant Solutions

Companion plants:Big, bold bedding plants, ideal to soften the harshness of large dahlias or to intersperse among Verbena bonariensis for a light, airy effect.

Viola x wittrockiana

Small-flowered Violas Hardy perennial or biennial

Neat, mat-forming perennials or biennials with slightly lobed, heart-shaped leaves and stems which are square in section. A constant run of small, pansy flowers is produced in a vast range of colours and patterns, ranging through blues, mauves, yellow, orange, purples and to almost black or tan red. Many have bi-coloured blooms or monkey faces; all have a sweet-sharp, honey fragrance.

Soil preference:Any reasonably fertile, not too dry

Aspect:Sun or part shade

Season of interest:Year round

Height and spread:Variable to 20cm × 30cm (8in × 1ft)

Companion plants:Adaptable to any situation – in containers, beds, rock gardens or even lining vegetables in a kitchen garden. Especially effective with spring bulbs or over-wintered plants such as polyanthus, primroses or wall flowers.

Verbena ‘Blue Lagoon’

Verbena Tender perennial

Oval, toothed leaves and semi-trailing stems which produce a summer-long succession of umbels bearing true blue flowers. Said to be resistant to mildew – a bugbear disease for bedding verbena – and to have sweet fragrance. A seed-raised series, but can be propagated from cuttings or divisions.

Soil preference:Fertile and free-draining

Aspect:Sun

Season of interest:Summer, autumn

Height and spread:25cm × 30cm (10in × 12in)

Companion plants:An excellent container plant to trail with such gold-leaf companions as Lamium ‘Golden Anniversary’ or with Lysimachia nummularia ‘Aurea’.

Zaluzianskya capensis

Night Phlox Tender annual

A member of the foxglove family which looks more like a pink or a campion! Sticky foliage on bushy plants is joined, in summer, by starry flowers with twin-lobed petals, which are crimson on the reverse, but white on their upper surfaces. The flowers open more fully at night when they become sweetly fragrant.

Soil preference:Any free-draining

Aspect:Sun

Season of interest:Summer

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

Companion plants:Try fusion planting, growing these South African beauties along with the equally sweetly scented and nocturnal Marvel of Peru or Mirabilis jalapa , and with tobaccos.

Begonia semperflorens

Tender perennial

Universally popular bedding plant with thick, fibrous roots, succulent stems and glossy, fleshy leaves which are rounded and may be bright green, or bronze or purple tinted. A constant run of flowers in colours ranging from scarlet, through reds and pinks to white. Good seed series are legion, for example, ‘Doublonia’ series and ‘Stara Mixed’.

Soil preference:Any

Aspect:Sun or part shade

Season of interest:Summer

Height and spread:To 30cm × 30cm (1ft × 1ft)

Companion plants:Best for bedding schemes, on account of their ability to make long-lasting carpets of colour. Also effective as texturing plants with grasses, perhaps, or for use in mixed containers with Helichrysum petiolare , Brachyscome or Senecio ‘Silver Dust’.

Brassica oleracea

Ornamental Cabbage, Ornamental Kale Hardy biennial

Valuable for their winter displays, ornamental cabbages and kales provide strong colours from their colourful foliage. The cabbages form loose but symmetrical rosettes with purple, rose-mauve, pink or creamy suffusions mixed with green. The kales have a more open, lax habit. The flowers, which follow in late spring, are yellow and usually clash with the coloured leaves.

Soil preference:Any

Aspect:Sun

Season of interest:Autumn, winter, spring

Height and spread:To 45cm × 30cm (1ft 6in × 1ft)

Companion plants:Useful for a strong colour display for winter but difficult to team with smaller flowers. Certain tulips, particularly in white, purple or pink shades, go surprisingly well.

Salpiglossis sinuata

Tender annual

A South American member of the potato family with slender habit, sparsely branched stems and slightly sticky foliage. During much of the summer, these plants produce a long succession of trumpet-shaped flowers. These are deeply veined and come in attractive, dusky colours ranging through yellows, brick red and orange to violet and purple-blue.

Soil preference:Any free-draining

Aspect:Sun

Season of interest:Summer

Height and spread:60cm × 30cm (2ft × 1ft)

Companion plants:Striking, characterful plants which need backing up with other, foliage-rich companions such as heliotropes, Centaurea cineraria or scented leaf pelargoniums.

Canna indica, C. iridiflora

Tender perennials

Large, coarse perennials with broad, oar-shaped, glossy surfaced leaves which unfurl like rolled banners; in some varieties these are dark-tinted or striated. The flowers, which resemble untidy irises, are produced in bunched panicles and come in shades of pink red, yellow, orange or white. The species C. iridiflora (pictured) grows taller and has gracefully hanging pink flowers.

Soil preference:Moist, fertile

Aspect:Sun

Season of interest:Summer

Height and spread:To 2.5m × 1m (8ft × 3ft)

Companion plants:Traditionally used as dot plants, in bedding schemes and effective when presiding over drifts of French marigolds, pelargoniums, Impatiens or nicotianas. Also fine in containers with Mexican salvias and Solanum rantonetii .

Cosmos bipinnatus, C. sulphureus

Hardy or near hardy annuals

Two variable species, with divided, often lacy foliage and an open, branching habit. The flowers are composite with yellow central florets and broad, showy outer ray florets which may be flat or, in some varieties such as ‘Seashells’, tubular. Flowers of C. bipinnatus range from deep rose or crimson through pinks to white. C. sulphureus comes in hotter colours ranging from yellow to coppery orange or near red.