Perennials & Annuals

This is an excerpt from the Book called “New Classic Gardens“ by Billy goodnick. Continue reading to learn more about Perennials & Annuals, thanks to the author.

Perennials & Annuals

With so much angularity the modern formal garden needs some sparkle, particularly in summer. And those gardens that are elegantly minimal can benefit from the inclusion of just one plant that alerts its appearance or sways in the breeze. Herbaceous plants fill this need and the best perennials can be integrated into a formal layout to soften it and give it a more contemporary feel. Bulbs and fast-growing annuals may also be used to ring the changes in a formal framework. (Quick effects with perennials and annuals, and the use of containers in the modern formal garden, are discussed.)

Herbaceous Perennials

Perennials are currently enjoying a revival of popularity. These plants have a reasonably long lifespan and will reappear every year, but they are less permanent and less rigid than shrubs, clipped or otherwise. On the whole, the perennials used in a modern formal context are not the flowers of the traditional herbaceous border but might includes species grown for their unusual dark foliage or flower colour, such as dark-leaved heucheras and Knautia macedonica. How you use them will depend on the spirit of the garden and its scales, so their habit, size, texture and colours may be chosen with this in mind. Those that are architecturally dramatic are referred to earlier.

Foliage Form

Neat effects can be achieved by using reliable perennials with clearly defined foliage as well as flowers. The satin-silver evergreen Astelia nervosa has sharply pointed but elegantly arching leaves; this plant grows to 60cm (2 ft) but its silver leaves spread to a diameter to 1.5 m (5 ft). Though needing a warm site, it should not be fully exposed not allowed to dry out completely. Sisyrinchium, striatum also grows with finely ormed leaves in a two-dimensional fan pattern, emphasized by spikes of cream flowers, 60 cm (2 ft) high, in early summer; the variegated form is particularly compact. Iris pallid ‘Argrntea Variegata’, with lilac flowers in late spring, is similar but slightly larger. All the irises have interesting foliage, but placing the right plant in the right place is important because some irises like their tubers baked by the sun and others prefer to have light shade.

Other foliage types include the hazy background provided by feathery leaves like that of the culinary fennels and Thalictrum lucidum, with cream flowers in summer, growing up to 1.2 m (4ft) high. The foliage of ferns or astilbes may be used to fringe latter shrubs with an attractive green lacy underskirt.

Colour

The formal garden is not the place for an uncontrolled ‘riot of colour’, nor for the multi-hued flamboyance of summer. It is basically green, with colour being used for a sympathetic background, harmonizing or contrasting with hard materials, or for powerful effects, to draw the eye. Colour can also be introduced to give scheme sophistication, for example restricting it to monochrome or pastel shades, or to energize the garden, using flamboyant, saturated primaries. The white and green garden is chic and appropriately formal in its restraint. Silver foliage belongs here too, with white flowers like the gracefully rhythmical flower spikes of tall Veronicastrum Virginicum album or white Madonna lilies (Lilium candidum). Luminous greys, like those of artemisias, are important too; they suit graveled schemes wee, creating a Mediterranean look. This colouring is ideal with white-rendered concrete walls, slate floors or in association with steel or lime-washed timber.

Moody blues, such as that of the elegant Campanula persicifolia (1m/3 ft tall), the shaded indigo of Aconitum ‘Spark’s Variety’ (1.5m/5 ft) or the inky blue Salvia x Sylvestris, Mainacht’ (45cm/ 18 in), have a cool effect which looks good with metals or slate; all are summer-flowering. With them plant steely eryngiums in galvanized containers. All of these would be superb if backed by yellow-or red-ochre rendered walls or in a more daring association with ultramarine-blue walls; they also look effective with flooring of terracotta tiles.

Plum-purples and brilliant magentas add richness and are dramatic against cream walls or blue-green slate paving. These colours are found in the midsummer-flowering Iris ‘Black Swan’(80 cm?2 ft 8 in tall0, Delphinium Black Knight Group(1m/ 3 ft 3 in), Geranium Psilsotemon ( 75 cm/ 2 ft 6 in) and the tender, deep maroon Cosmos atrosanguineus ( 60 cm/2 ft), flowering in late summer. If contrast is required, black floor tiling, blue-pink granite sets or dark timber would intensify the effect.

Hot, earthy colours are powerful, like those of late-summer Helenium ‘Coppelia’ (1.2m/ 4 ft) and the midsummer-flowering Hemerocallis ‘Morocco Red’ and Achillea millefolium ‘Paprika’ (both 60 cm/2 ft). Plant these with bronze-leaved heucheras, to blend with brick and terracotta flooring or earth-coloured rendering. Dahlias will enrich any of these schemes towards the end of the season.

Texture

Texture has become a significant modern theme. Where the design is formal and the surfaces clearly geometric, it is the style of planting which will soften such severity. So hazy plants with tiny flowers, like gypsophila, or the wisp-fine foliage of fennel (Foeniculum Vulgare), are in demand for their visual texture, performing as gently as a layer of filmy organza. Light is the key: as the sun move around, the plants change character. Lit from the front, they are more noticeable but lit from behind the silhouette becomes a transparent decent through which other plants do features may be viewed. Texture can be tactile, too, like the furry leaves of Stachys byzantia. Irresitibly strokable plants like these soften the perception of the most clinical of layouts.

Ornamental grasses offer wonderful textural properties; they also have a long, late season and many can remain all winter to be sugared with frost. Of all garden plants, they are the most responsive to changing light effects, appealing to the senses of sight, sound and touch, ideal subjects for they understand of modern gardens. Their flowers are often a myriad of tiny insubstantial culms, as with the 70cm (2 ft 3 in) high evergreen tufted hair grass (Deschampsia cespitosa’ Goldtau’), flowering early in summer. Others are more solidly structured, like the rounded fountain grasses (Pennisetum), especially the lovely P. Orientale with a height and spread of 45 cm (18 in), whose late-summer flowers resemble furry foxtails. Some grasses are mop headed, resembling tousled fine hair, such as the 60cm (2 ft) high, summer-flowering feather grass (stipa tenuissima). Others stand rigidly erect, like Calamagrostis x acutiflora”Stricta’ which, on upright stems of 1.5m(5 ft), provides delicate but firm contrast with floating midsummer grass flowers.

In the modern formal context ornamental grasses have proved to be ravishing animators of otherwise static scenes. Where clipped evergreen definition has a welcome simplicity, lines or grid patterns of grassy textures affect the scheme so that by late summer the picture is one of constant movement, with grass foliage responding to every air current while above hover fine hazy flowers, flickering with light.

Annual Effects

All gardens remind us of the passage of time and this continues in the new styles as well. Once the formal framework is established, the look of the garden alters seasonally, first with the spring freshness of bulbs, then through the summer high with flower colour. Autumn gives the garden a final warmth with its leaf colour and fruit. So during the year the whole character of the garden can change, making this a unique art form.

Bulbs like tulips lend themselves naturally top the geometry of the modern scene. With their sophisticated colours, they are a rich sight in spring and looks magnificently form, all when ranked in lines. They are also ideal for sparse planting effects, using small groups in selected spaces.

Lilies will admirably fir the bill for summer. There are many species and hybrids, most of which prefer full sun and need good drainage; putting the bulbs on a mound of sharp sand is helpful. Alliums too will add formal character in summer, particularly the tall drumstick forms like Allium giganteum. As the season progresses, agapanthus will provide tall blue or white flowers emerging from green, strap-like foliage. All these carry themselves with a dignity appropriate to formal gardens. Plant bulbs at the right depth, usually two and a half times the bulb’s height. If putting in large, expensive bulbs such as lilies treat them against fungus and mice with a proprietary powder. Check soil drainage and plant them on coarse sand, if necessary, as in the case of lilies.

Some annuals with tall spikes have the same potential gravitas as the bulbs just referred to. Repeated upright forms suit an organized layout, so look for tall, slim flower spikes like those of foxgloves or Moluccella laevis. Colour can bring a formal plan alive as well and some annuals will do this almost instantly, such as antirrhinums or dahlias.