Plant Solutions

Cleome hassleriana

Spider Flower Near hardy annual

A tall, rangy annual with decorative, seven-lobed palmate leaves held on short stalks along the tall, erect spike which terminates in a series of fragrant, distinctive white or pink flowers whose narrow petals and elongated stamens and stigma give the impression of colourful, long-legged spiders. Native of South America.

Soil preference: Any fertile, free-draining, not too dry

Aspect: Sun, part shade

Season of interest: Summer

Height and spread: 1.2m × 30cm (4ft × 1ft)

Companion plants: Ideal for the border back or to grow among tall perennials such as perennial asters since it brings earlier colour. The exotic appearance makes it a good companion to broad-leaved plants such as banana, canna or hedychiums (ginger lilies.)

Atriplex hortensis

Red Orache Hardy annual

An easy annual, distinguished – especially when young – by its conspicuous slightly downy-textured, rich purple leaves which are oval, pointed and borne on flexible stems. Some of the early colour intensity is lost as the plant matures to produce, in summer, foxtail flowers which are brownish green. Self-seeds freely but is easy to control.

Soil preference: Any

Aspect: Sun, part shade, shade

Season of interest: Spring, summer

Height and spread: 1m × 30cm (3ft × 1ft)

Companion plants: Prettiest when allowed to dot itself among other plants in mixed borders or among shrubs. The foliage contrasts dramatically with the silver grey of young artemisias or with the gentle gold of Milium effusum ‘Aureum’.

Silene coeli-rosa (Viscaria oculata)

Hardy annual

A hairless, reasonably erect annual with slender stems and narrow, oblong leaves. The small but showy, pale pink or two-tone pink and white flowers are produced in profusion on longish stems for much of the summer. Tolerant of hot, dry conditions and usually trouble-free.

Soil preference: Any free-draining

Aspect: Sun

Season of interest: Summer

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

Companion plants: Prettiest with other annuals such as nigellas, poppies or Anagallis, but also handy to blend with other low growing perennials such as pinks and carnations, sedums, Origanum rotundifolium and Euphorbia myrsinites.

Rhinanthus minor

Hay Rattle, Yellow Rattle Hardy, semi-parasitic Annual

An interesting member of the foxglove family which can only germinate in the presence of host plants – grasses – from which it derives much of its sustenance during the early part of its life. The narrow, toothed leaves, bright yellow, lipped flowers and semi-translucent, pale green calyces make this a distinctive grassland species.

Soil preference: Moist, grass sward

Aspect: Sun

Season of interest: Summer

Height and spread: 30cm × 15cm (1ft × 15cm)

Companion plants: The ‘impoverishing’ effect Rhinanthus has on grass growth is of great benefit because it enables other broad-leaved flowering plants to colonize more easily. Wonderful with Cardamine pratensis, cowslips, cranesbill and knapweeds.

Blue Centaurea cyanus produces an attractive picture when combined with red poppies, corn chamomile and corn marigold.

Planting Naturalistic Schemes

Many annuals which occur in the wild are opportunist plants which grow wherever the ground is disturbed. As fieldcrop weeds, many of them occur worldwide and among the most beautiful are those which colonize the ground among growing cereal crops. This cornfield scene, with its red poppies, blue cornflowers, yellow corn marigold and daisy-like corn chamomile would be simple to reproduce as part of a naturalistic planting scheme in an informal garden. Some wild annuals, however, may be too invasive to risk introducing into a garden – especially a small one.

To avoid creating problems with over-exuberant self-seeding, beds of annuals or ‘arable patches’ imitating cornfields should be contained. Solid pathways around their edges or other non-cultivable ground surfaces can help to prevent seed spread but may compromise the natural appearance. Annuals that are allowed to spill over their boundaries by self-seeding can be far more beautiful than those regimented in strict beds.

biennials

Biennials for spring

Biennials for summer

Biennials for special effects

Biennials beneficial to wildlife

Biennials for spring

Myosotis sylvatica

Forget-me-not Hardy biennial

Narrow, bright green leaves that form neat clumps over winter are joined from early spring by expanding spikes of tiny, pale centred, blue flowers. The first flowers nestle among the leaves, but as spring advances, the stems extend, creating a soft blue haze. A ready self-seeder. ‘Blue Ball’ is the most widely grown variety, but other seed series include ‘Victoria’ which has blue, white or pink flowers.

Soil preference: Any well-drained

Aspect: Sun or part shade

Season of interest: Spring, early summer

Height and spread: Up to 30cm × 40cm (1ft × 1ft 4in)

Companion plants: One of the finest companions for tulips, since it creates a soft, blue base. Charming when dotted among spring perennials such as Lathyrus vernus, yellow doronicums or polyanthus.

Erysimum cheiri

Bedding Wallflowers Hardy biennial

Shrubby biennial or shortlived perennial with narrow, evergreen leaves and from mid-spring spikes with bold-coloured, four-petalled flowers, which are sweetly fragrant. Dwarf bedding varieties include the mixed ‘Persian Carpet’. ‘Fire King’ is a taller orange red variety and ‘Blood Red’ an old breed with deep blood red flowers.

Soil preference: Any, preferably alkaline

Aspect: Sun

Season of interest: Spring

Height and spread: Up to 60cm × 40cm (2ft × 1ft 4in)

Companion plants: Pretty when bedded with tulips, but also handy for gap filling in a mixed or herbaceous border. Wallflowers work well with emerging lupin foliage, with tulips or with the hazy blue flowers of Brunnera macrophylla.

Erysimum

Perennial Wallflowers shortlived perennials, can be grown as biennials

Shrubby wallflower varieties with narrow, sometimes blue-grey leaves and a steady succession of stiff flower spikes held well clear of the leaves, and bearing four-petalled blooms in mauve, bronze, cream, yellow or red. Erysimum ‘Bowles Mauve’ is the best known but ‘Sunlight’ has yellow flowers and ‘Harpur Crewe’ small, double yellow, richly fragrant blooms.

Soil preference: Free-draining

Aspect: Sun

Season of interest: Spring, summer

Height and spread: Variable to 75cm × 60cm (2ft 6in × 2ft)

Companion plants: Good in a dry gravel or Mediterranean garden, with yellow-flowered Genista lydia and silver-leaved shrubs and herbs.

Digitalis purpurea

Foxglove Hardy biennial

Large, downy basal leaves in the first year are followed by tall, slender spikes furnished with many tubular downward-hanging flowers. The typical species has purplish pink flowers whose throats are thickly spotted with rusty marks, but garden forms come in a range of colours from white, through pale pink and apricot to deep purple.

Soil preference: Well-drained, but not too dry

Aspect: Shade or part shade

Season of interest: Late spring, early summer

Height and spread: Up to 2m × 60cm (6ft 6in × 2ft)

Companion plants: Excellent for woodland planting or to fill spaces between shrubs. Foxgloves are also lovely in cottage-style gardens, alongside cranesbills, old fashioned roses or with columbines.

Smyrnium perfoliatum

Biennial

A biennial with branched, winged stems and from mid-spring, showy, bract-like leaves which surround the flower umbels and are a vivid golden green. Lovely with the light coming through them, but this is an invasive plant which seeds a little too freely.

Soil preference: Any, not too damp

Aspect: Sun or shade

Season of interest: Spring

Height and spread. 1m × 45cm (3ft 3in × 1ft 6in)

Companion plants: Good for filling up spaces below trees, or allowing to spread with such other umbelliferous plants as sweet cicely or cow parsley. Also handsome when planted with red tulips, or with purple honesty Lunaria annua.

Hesperis matronalis

Dames Violet, Sweet Rocket Biennial or shortlived perennial

Cabbage family member with narrow leaves held on stout flower spikes that are topped with generous clusters of four-petalled fragrant blooms, the perfume being especially strong at twilight. Colours range from white, through pale mauve to soft purple. Replace flowered plants with self-sown seedlings.

Soil preference: Any, moist

Aspect: Sun or part shade

Season of interest: Spring, early summer

Height and spread: 1m × 30cm (3ft × 1ft)

Companion plants: A lovely species whose pale colours which show up well in poor light, and which go well with such bolder-hued early perennials as lupins, campanulas or even oriental poppies.

Biennials for summer

Campanula medium

Canterbury Bells Hardy biennial

The showiest of all bell flowers, with rough-textured, simple leaves and thick, ribbed stems. The stems develop into generously endowed spikes whose huge, tubular bell flowers may be shades of blue, pink or white. ‘Cup and saucer’ varieties have a bell flower resting on a petal-like, coloured calyx. Double-flowered varieties are available from seed catalogues.

Soil preference: Well-drained

Aspect: Sun

Season of interest: Summer

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

Companion plants: A perfect cottage plant, showy but in gentle colours and along with sweet Williams, ideal for bridging the gap between spring and midsummer, following on from wallflowers. Beautiful with roses!

Salvia farinacea

Mealy Sage Tender biennial

Technically a perennial, but grown as a tender biennial or annual, the leaves are glossy but the flower stems are coated with a white mealy substance. The lipped flowers, produced throughout summer, are purple, blue or white. Salvia farinacea ‘Victoria’ is a popular bedding plant.

Soil preference: Any, fertile but free-draining

Aspect: Sun

Season of interest: Summer

Height and spread: 1m × 60cm (3ft × 3 ft)

Companion plants: Attractive when included in a tropical mix, perhaps with cannas, bold grasses such as Chasmanthium or ornamental sorghums.

Ratibida columnifera

Mexican Hat Biennial or shortlived perennial

A member of the daisy family from Mexico, with divided leaves and erect stems bearing flowers whose broad, yellow, or red and yellow sterile ray florets surround an extended central cone. Viewed from the side, these Rudbeckia relatives resemble the sombreros worn by Mexican bandits in cowboy films.

Soil preference: Any well-drained, but not too dry

Aspect: Sun

Season of interest: Summer

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

Companion plants: A delightful cottage garden plant whose shape contrasts well with campanulas, delphiniums or with perennial asters.

Lysimachia atropurpurea

Hardy biennial or shortlived perennial

A striking, if somewhat sparse growing species with pewter-suffused foliage when young and, during mid-summer, narrow spikes of deep purple-red flowers which contrast with the grey-green tones of the leaves. From the distance, the flowers look black and disappear, but close-to, especially if used as cut flowers, they are superb.

Soil preference: Fertile, free-draining

Aspect: Sun

Season of interest: Summer

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

Companion plants: Best planted with light-coloured foliage plants such as Artemisia ludoviciana or Convolvulus cneorum so that the sombre blooms can make a strong contrast.

Oenothera biennis

Evening Primrose Biennial

Broad, pointed leaves form loose rosettes producing, in their second year, tall, somewhat lax stems with large pale yellow blooms that open at twilight and are spent by the following midday. May be a nuisance self-seeder, but a late summer delight.

Soil preference: Any

Aspect: Sun or part shade

Season of interest: Summer

Height and spread: 1.2m × 45cm (4ft × 1ft 6in)

Companion plants: One to dot about or allow to come up where it will in an informal planting scheme. Especially good among the soft mauves, purples and blues of perennial asters or in a late season annual border.

Scabiosa atropurpurea

Mournful Widow, Egyptian Rose Biennial

Lobed or divided leaves and thin, branched stems carry, in summer and early autumn, a long succession of pincushion-like flowers in dusky maroon or near black. The form ‘Chile Black’ is dark crimson, ‘Chile Sauce’ is rose red and ‘Salmon Queen’ a deep salmon pink.

Soil preference: Any fertile soil

Aspect: Sun

Season of interest: Summer

Height and spread: 90cm × 45cm (3ft × 1ft 6in)

Companion plants: Beautiful grown with summer annuals such as corn cockle or field poppies, and with taller ornamental grasses like Deschampsia.

Biennials for special effects

Eryngium giganteum ‘Miss Willmott’s Ghost’

short-lived perennial

A very large perennial with prickly leaves and stems. The leaves are suffused with silvery white and each dome-shaped, thistle-like flower carries a spiky ruff at its base. The common name arises from the habit of Edwardian garden guru Ellen Willmott who, presumptuously, scattered seeds of it in other people’s gardens.

Soil preference: Any fertile

Aspect: Sun or part shade

Season of interest: Summer, autumn

Height and spread: 1.5m × 80cm (5ft × 2ft 8in)

Companion plants: Plants of great character, making strong focal points in mixed borders. Useful for lightening up dark evergreen shrubs at the back of borders, or to dot among tall perennials such as Verbena bonariensis and with big grasses.

Geranium maderense

Madeiran Cranesbill Tender biennial

Palmate leaves grow from a stumpy base, forming a large, impressive rosette. When the necessary size has been reached, a big branched flowerhead forms and erupts into a spectacular display of rich cerise to rosy purple flowers, each with a more intense eye. Once seed has formed, the plant dies. Must have winter protection.

Soil preference: Any not too dry, but well-drained

Aspect: Part shade

Season of interest: Summer

Height and spread: Up to 1.3m × 1m (4ft × 3ft 3in)

Companion plants: Best in a container in cold regions. Perfect in the company of ferns or of broad-leaved, shade-loving plants such as the larger hostas.

Meconopsis napaulensis

Technically a perennial but seldom survives flowering

As valued for the beautiful rosettes of felty lobed leaves, each one covered in rust-coloured hairs, as for the huge flower spikes which will grow well over 2m (6ft) before producing a generous supply of poppy flowers in pinkish red, purple or dusky blue.

Soil preference: Preferably lime-free, not too dry

Aspect: Shade or part shade

Season of interest: Summer.

Height and spread: 2m × 75cm (6ft 6in × 2ft 6in)

Companion plants: A plant for the woodland garden, or at least for dappled shade and therefore wonderful with foxgloves or perhaps teamed up with other Himalayan poppies such as Meconopsis grandis.

Digitalis

Foxglove Hardy biennial or short-lived perennial

Heather Angel

The common foxglove (Digitalis purpurea) has several equally dramatic and unusual cousins. One of the finest is D. grandiflora (pictured), which has bold, dark green tooth-edged leaves and early summer flower spikes of large butter yellow blooms. D. ‘Carillon’ is similar but shorter and D. × mertonensis, a cross between D. grandiflora and D. purpurea, has crushed strawberry blooms.

Soil preference: Any free-draining

Aspect: Sun or part shade

Season of interest: Summer

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

Companion plants: Foxgloves are excellent for adding height and flower power to shady borders. Digitalis grandiflora works particularly well in a cool-colour planting scheme with blue, white and clear yellow flowers.

Echium russicum

Red Bugloss Marginally tender to hardy biennial

R. Coates

Tidy rosettes of narrow, dark grey-green leaves develop during autumn and winter. During the following spring and early summer, rigid spikes appear, carrying narrow leaves along their lengths and, later, clusters of small, rose-red flowers which are irresistible to bees. The plants must be in a free-draining, sheltered spot to survive winter.

Soil preference: Any well-drained

Aspect: Sun

Season of interest: Summer

Height and spread: 45cm × 30cm (1ft 6in × 12in)

Companion plants: Best in bold groups where the spikes can make a contrast with lower growing early summer plants such as helianthemums, Verbascum ‘Letitia’ or Alchemilla.

Petroselinum crispum

Parsley, Curled Parsley Hardy biennial or short-lived perennial

Familiar kitchen herb which also makes a first rate ornamental foliage plant. The leaves are vivid, emerald green, tightly curled and crisped, or flat, ferny and much divided. Sprays of greenish umbels appear in late summer but are not particularly decorative. Will self-seed.

Soil preference: Any

Aspect: Sun or part shade

Season of interest: Year round

Height and spread: Foliage 25cm (10in), flower to 60cm (2ft)

Companion plants: Cooling foil for bright, hot coloured flowers such as tulips in spring, annual poppies, pansies or marigolds in summer.