Plant Solutions

Companion plants: A beautiful foil for showy herbaceous plants such as scabious, cornflowers, Linum or Oenothera.

Eschscholzia californica

Californian Poppy Annual or shortlived perennial

A beautiful combination of blue-green, lacy foliage and bright, silky-textured flowers makes this American native a valuable plant, especially for a dry garden. The wild species has bright orange flowers, but seed selections come in a range of sunset hues from cream or primrose yellow, through peachy tones to burnt orange. Best in free-draining soil.

Soil preference: Dry, not too fertile

Aspect: Sun

Season of interest: Summer

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

Companion plants: The orange form makes a stirring companion to such bronze-tinted grasses as Stipa tenuissima or the sedge Carex buchananii. Also good in a gravel garden, where its misty foliage and silky petals will soften hard textures.

Geranium robertianum

Herb Robert Annual

An invasive annual with spreading habit, pungentsmelling, ferny foliage and a long run of tiny, pink, five-petalled flowers. The albino form, ‘Album’, is more distinctive. A thug in the wrong place, but charming when allowed to self-sow in drifts in gravel or along the edges of a path.

Soil preference: Any free-draining

Aspect: Sun or part shade

Season of interest: Spring, summer, autumn

Height and spread: 20cm × 40cm (8in × 1ft 4in)

Companion plants: Naturalize this one with other gravel or paving crack plants such as Viola riviniana or Alchemilla.

Annuals for very rich soil

Consolida ajacis

Larkspur Annual

Classic cornfield annual which has been bred to improve height, standing power, and colour range. The leaves are finely divided and the tall, straight stems are furnished with spurred flowers in shades of pink or blue or white. Easy to raise from seed sown in autumn or spring, directly where they are expected to flower.

Soil preference: Fertile, well-drained

Aspect: Sun

Season of interest: Summer

Height and spread: Up to 1m × 30cm (3ft 4in × 1 ft)

Companion plants: Good as a cut flower and therefore effective grown among vegetables in a kitchen garden or in a mixed border. Attractive with roses, where the straight spikes make a strong contrast and where the blues and pinks of the flowers harmonize.

Helianthus annuus

Sunflower – large varieties Annual

Biggest of the hardy annuals and raised as food crops in Central America since prehistoric times. The stout stems are strong enough to carry the massive flowers and seed heads without support. Some ornamental varieties are sterile and bear no pollen. Field crop sunflowers are golden yellow, but cultivated forms include such colourful series as ‘Ring of Fire’, whose flowers have concentric ring patterns in hues of dusky red and yellow, or ‘Moonshadow’, whose flowers are cream.

Soil preference: Rich, fertile

Aspect: Sun

Season of interest: Summer

Height and spread: Up to 3m × 1m (10ft by 3ft)

Companion plants: Useful plant to create a temporary screen, or to use as accent plants in a bedding scheme, cottage border or kitchen garden.

Linum grandiflorum

Flowering Flax Annual

Slender, almost wiry stems with narrow, pointed leaves bear a long succession of disc-shape flowers up to 4cm (1¾in) across. In the wild, these are rosy purple, but seed selections include ‘Bright Eyes’, whose flowers are white with conspicuous wine red centres, and ‘Rubrum’, whose petals are a deeper rose with dark crimson centres.

Soil preference: Any, free-draining

Aspect: Sun

Season of interest: Summer

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

Companion plants: The waving stems and frail flowers look delightful among coloured grasses or sedges such as Carex comans or Molinia caerulea. Also lovely when naturalized among low-growing shrubs in a Mediterranean-style planting scheme.

Annuals for gap-filling in mixed borders

Cynoglossum amabile

Chinese Forget-me-not Annual

J. Swithinbank

Narrow, pointed leaves on branched stems are joined in early and mid-summer by clusters of small forget-me-not flowers in an intense blue. Pink and white flowered varieties are also available. The seeds are large and exceptionally hard.

Soil preference: Fertile, free-draining

Aspect: Sun or part shade

Season of interest: Summer

Height and spread: 50cm × 30cm (20in × 12in)

Companion plants: Blue forms contrast sharply with the yellows of verbascums or, from later sowings, goldenrods and yellow daisies such as rudbeckias and heleniums. The intense blue would also relieve the monotony of a cool, silvery or white theme.

Datura inoxia

Downy Thorn Apple Annual

A large, much branched, characterful annual with big, oval leaves which are downy and slightly tacky to the touch. The huge trumpet flowers – 15cm (6in) or more long – are purple tinged when in bud, but open to a soft white. In the evening and at night they are heavily scented.

Soil preference: Any fertile soil

Aspect: Sun

Season of interest: Summer, autumn

Height and spread: Up to 1m × 1m (3ft 3in × 3ft 3in)

Companion plants: One to grow on its own, but for a heady cocktail of night fragrance, plant with fragrant tobacco Nicotiana affinis and the vanilla scented heliotrope.

Malope trifida

Annual Mallow Annual

Similar to annual Lavetera trimestris, but slightly smaller with more downy, heart-shaped leaves that hang down as the plant matures. Big saucer shaped flowers appear in succession throughout summer and colours in the various seed selections range from dusky and rose pink to bright magenta, deep plum and white.

Soil preference: Fertile but well-drained

Aspect: Sun

Season of interest: Summer

Height and spread: 50–75cm × 45cm (1ft 8in–2ft 6in by 1ft 6in)

Companion plants: Better than lavatera for mixing with other such hardy annuals as cornflowers, clarkia, larkspurs, Convolvulus tricolor and corn cockle.

Zinnia elegans

Annual

The species has been used to develop a colourful range of tender annuals, with simple leaves, slightly rough to the touch, and flowers with attractive layered florets, often with dark ochre or yellowish fertile centres. Flower colours include white, yellow, pink, mauve, orange, red, maroon and even pale green with a variety of flower forms from single to pompon.

Soil preference: Fertile, free-draining but not too dry

Aspect: Sun, shelter

Season of interest: Summer

Height and spread: From 20cm × 30cm to 1m × 50cm (from 8in × 3ft to 3ft 3in × 1ft 8in)

Companion plants: As desirable for cutting as for garden use, Zinnias will benefit from softer, more diffuse shapes nearby. Goldenrods add extra summer yellow, with a contrasting texture. Pale mauve or blue varieties of perennial aster will tone down the zinnias’ jazz.

Borago officinalis

Borage Annual

Large, heart-shaped to oval puckered, hairy leaves and thick, fleshy, branched stems carry myriads of small, star shaped flowers which are intense sky blue, with pale centres and dark, spiky stamens. A rapid annual which self-seeds copiously.

Soil preference: Any

Aspect: Any

Season of interest: Summer, autumn

Height and spread: Up to 1m × 75cm (3ft 3in × 2ft 6in), usually smaller

Companion plants: Beautiful anywhere but easily pulled out if not welcome. Herbs such as lavenders, herbaceous perennials, shrubs, large grasses, roses and bedding plants all make great companions.

Phacelia tanacetifolia

Fiddleneck Annual

Handsome American species, often used as a ‘green manure’ crop. The compound leaves, reminiscent of Jacob’s Ladders, create a ferny effect as the branched stems develop and lengthen. Buds are carried on tightly curled scapes, like violin heads, which uncurl and straighten as the violet blue flowers open. A free seeder.

Soil preference: Any, not too wet

Aspect: Sun or part shade

Season of interest: Summer

Height and spread: Up to 1m × 60cm (up to 3ft 3in × 2ft)

Companion plants: Another charming annual to sow in drifts among grasses or naturalistically planted perennials. The soft lavender-blue haze they create is also pretty with creamy or sunset-hued achilleas or among blue cranesbills.

Annuals for containers

Antirrhinum pulverulentum

Trailing Snapdragon Half hardy perennial, grown as an Annual

A compact, but trailing plant with oval, dull-green leaves and a long succession of ‘snapdragon’ flowers whose lips gape when gently pinched. Hybrids include the series ‘Pendula Lampion’ with pale pink, white or purplish flowers and pale yellow markings. Antirrhinum hispanicum subsp. hispanicum has silvery grey leaves and purplish pink blooms.

Soil preference: Any free-draining

Aspect: Sun

Season of interest: Summer and autumn

Height and spread: 15cm trailing 30cm (6in trailing 1ft)

Companion plants: Equally effective in hanging baskets, window boxes or alpine troughs. Their pastel hues blend gently with the grey-green foliage of Helichrysum petiolare or with white-variegated Glechoma hederacea ‘Variegata’.

Celosia argentea

Cockscomb or Wool Flower Tender annual or shortlived perennial

Vigorous, soft-textured plants with pointed leaves and successions of bold, highly coloured plume-like flowers in vivid shades including red, orange, yellow and purple. ‘Fresh Look Red’ has scarlet flowers. The mixed ‘Look Eternal Flames’ has either bright yellow or burning red flowers, accompanied by foliage which is green or deep purple-bronze.

Soil preference: Free-draining but moist and fertile

Aspect: Sun

Season of interest: Summer

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

Companion plants: Their sub-tropical looks and strong flower colour make these plants good companions for Solenostemon (Coleus). Also try cooling with deep blue bedding lobelias.

Nemesia strumosa

Nemesia Tender Annual

J. Swithinbank

A South African member of the foxglove family, whose main features are the massed flowers in bright sunny colours which include orange, red, white, pink and yellow. ‘Nebula Mixed’ has hot, single colours whereas ‘KLM’ is a blue and white bicolour. The series ‘Sundrops’ has a remarkably long flowering period.

Soil preference: Any moisture retentive and fertile

Aspect: Sun

Season of interest: Summer

Height and spread: Variable to 30cm × 15cm (1ft by 6in)

Companion plants: The hot colours benefit from the cooling effect of blue-flowered bedding lobelia or a blue variety of Laurentia.

Phlox drummondii

Annual Phlox Tender Annual

Delicate plants, with rather weedy growth and nondescript simple leaves produce large heads of brightly coloured, disc-shaped flowers, often with contrasting centres. Superb when in full bloom but the flowering season can be brief. ‘Phlox of Sheep’ is an excellent series, with flowers in sunset hues; ‘Silver Blossom’ has mauve, dusky pink and even beige suffusions; and the petals of ‘Twinkle Stars’ are white-edged picotee types.

Soil preference: Free-draining but fertile

Aspect: Sun

Season of interest: Summer

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

Companion plants: Best when backed up by the strong characterful foliage of Plectranthus or when planted with such annual grasses as Briza maxima and Lagurus ovatus.

Sanvitalia procumbens

Creeping Zinnia Tender Annual

Trailing stems with simple, deep-green leaves and a summer-long succession of abundant small daisy flowers with broad, orange or yellow sterile ray florets and deep green or dark centres. The variety ‘Irish Eyes’ is golden yellow with glowing green flower centres. ‘Orange Sprite’ is dwarfer, with bright orange semi-double flowers whose centres are dark.

Soil preference: Any fertile and free-draining

Aspect: Sun

Season of interest: Summer

Height and spread: 15cm (6in), spreading 30cm (1ft)

Companion plants: Good in a bold colour scheme with perhaps compact varieties of nasturtiums and purple-leaved basil. Excellent contrast with dark blue trailing lobelia.

Dorotheanthus bellidiformis

Livingstone Daisy Tender Annual

A South African member of the ice plant family with small, fleshy leaves, mealy in texture, and a long succession of bright, daisy-like flowers in day-glow colours. ‘Apricot Tutu’ has pinkish sunset-hued flowers, but ‘Sparkles’ has a wider range including pale cream, purplish pink and orange, many flowers being bicoloured. The flowers will only open in full, direct sunlight.

Soil preference: Free-draining, not rich

Aspect: Full sun

Season of interest: Summer

Height and spread: To 15cm × 25cm (6in × 10in)

Companion plants: Good on their own in a hot, dry container in the sun or to add colour to such succulents as echeverias, sedums or sempervivums.

Annuals good for cut flowers

Rudbeckia hirta

Half hardy perennials grown as annuals

Dwarf, intermediate and tall hybrids of this North American genus have dark stems and simple leaves, lightly covered with short hairs. The daisy flowers, with their conspicuous ray florets and dark central cones, come in warm tones from yellow through to mahogany. Good cutting varieties include the double-flowered ‘Cherokee Sunset’, spidery-bloomed ‘Chim-chimenee’, and the green and golden ‘Irish Eyes’.

Soil preference: Fertile, moisture-retentive and heavy but drained

Aspect: Sun or part shade

Season of interest: Summer, autumn

Height and spread: 15–60cm × 30cm (6in–2ft × 1ft)

Companion plants: Use these plants to extend summer displays and blend with late flowering blue and purple salvias and perennial asters. They are also bewitching with soft, flowing grasses or sedges such as bronze leaved Carex and Stipa arundinacea.

Antirrhinum majus tall varieties

Half hardy to hardy perennial, usually grown as an annual

Familiar snapdragons such as ‘Axiom Series’ which have been bred to grow as tall plants, each with a straight, single stem ending in a long spike bearing the flowers in a broad colour range, including red, pink, yellow and bicolours. Plant in a sheltered spot or raise under glass.

Soil preference: Fertile, well-drained

Aspect: Sun, often raised under glass

Season of interest: Constant, depending when planted

Height and spread: To 75cm (30in)

Companion plants: Pretty plants for a summer kitchen garden, along with such cutting flowers as marigolds, larkspurs, dahlias and Gladiolus.

Helianthus annuus

Sunflower – pollen-free varieties Hardy annual

Single or branched stems may grow from a single seed, furnished with broad, slightly hoary, simple leaves and massive flowerheads with bright yellow, orange or maroon ray florets. Selections for cutting include pollen-free ‘Bees Knees’, whose flower colours include orange, lemon yellow, rich gold and deep reddish brown and orange, as well as the powderpuff-like ‘Double Shine’.

Soil preference: Fertile, free-draining

Aspect: Sun

Season of interest: Summer

Height and spread: Variable to 2m × 30cm (6ft × 1ft)

Companion plants: Too dominant to harmonize with other annuals, but very effective when planted as short-term screens or along walls or hedges. Pollen-free varieties are NOT GOOD for wildlife.

Dianthus barbatus ‘Summer Sundae’

Annual Sweet William Hardy annual or biennial

An annual form of the familiar sweet William described here. Although spring-sown seed will produce flowers the same season, autumn-sown plants will grow a little larger and flower for longer. A valuable variety, though, for speedy cut flowers. The multi-headed flowers are sweetly fragrant and last well in water.

Soil preference: Any free-draining

Aspect: Sun

Season of interest: Summer

Height and spread: 45–60cm × 20cm (18in–2ft × 8in)

Companion plants: All sweet Williams make excellent border plants, as they are at home with most perennials. Particularly effective with such flowery summer annuals as cornflowers, larkspurs, marigolds and poppies.

Callistephus hybrids

Bedding Asters Half hardy annual

Popular both as bedding or for cut flowers, these daisy relatives have showy ray florets in pink, purple, white, cream and wine red. Many different forms are widely available. Good cutting kinds, with long lasting qualities, include ‘Truffaunt’s Peony Mixed’, whose petals are incurved, and ‘Super Chinensis’, which has single flowers with bold, yellow centres.

Soil preference: Fertile, free-draining

Aspect: Sun or part shade

Season of interest: Summer

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

Companion plants: If varieties are chosen with gentle colours, asters make great companion plants for red, pink or white bedded roses. Also fine in rows in a kitchen garden.

Molucella laevis

Bells of Ireland Half hardy annual

A member of the deadnettle family whose main features are the large, pale green, bell-shaped bracts which surround the tiny, off-white flowers, and which persist for the whole growing season. The foliage is unremarkable. Stems with the bracts are as effective when used dried as when they are fresh.

Soil preference: Fertile, free-draining

Aspect: Sun

Season of interest: Summer

Height and spread: 60cm × 25cm (2ft × 10in)

Companion plants: Normally grown for cutting though Molucella can look attractive among white flowers or with silvery foliage plants such as Artemisia ludoviciana or Salvia farinacea ‘Victoria’.