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