Landscape architect Capability Brown was fond of placing deep purple copper beech trees among the greens of oak and willow; the variation of leaf colour slowed the viewer’s gaze and offered focal points within the landscape. I was reminded of the power of this simple trick in my own humbler herbaceous border. This spring I planted tubers of dahlia ‘Bishop of York’ for their pale yellow flowers, but, come summer, it was their dark foliage that made the most impact. The near-black leaves offered a foil for the flowers in front and behind, making the rudbeckia and scabious pop, but also breaking up the continuous greenery. My small border appeared a good deal larger.
If you have room, dark-leaved trees are hugely worthwhile as a backdrop. Against a fence or an open view, flowers can fade; against deep colour they become emboldened. Besides copper beech, which, for its scale, belongs in a park, favourites include black cherry plum (Prunus cerasifera ‘Nigra’), red Norway maple (Acer platanoides ‘Royal Red’) and the purple filbert hazel, Corylus maxima ‘Purpurea’.
For more modest spaces plenty of shrubs serve the same function: smoke bush (Cotinus), Japanese barberry (Berberis thunbergii), Physocarpus (‘Diabolo’ or ‘Lady in Red’, in particular) and, probably best of all, the dark cultivars of black elder (Sambucus nigra). A good planting combination is the slender yellow flower spikes of Ligularia przewalskii against a thick wall of black elder leaves.
On a herbaceous level, the low-growing black mondo grass Ophiopogon planiscapus ‘Nigrescens’, the many dark-leaf heucheras, and purple varieties of the succulent perennial Hylotelephium telephium. Here are a few hardy alternatives, most of which can be planted now for next year’s seasons.
Spring
Ajuga ‘Black Scallop’
Ajuga reptans is one of those creeping perennials you forget all about until early spring, when you spot it spreading low and lively while other leaves are still getting going. In the season of bright flowers, the chocolaty foliage offers unparalleled contrast, not least for its own vibrant blue flower spikes. Plant at the front of the border, or as an underplant for narcissi, tulips and aquilegia. jacksonsnurseries.co.uk
Cow parsley ‘Ravenswing’
Few dark plants rival Anthriscus sylvestris, a stunning form of cow parsley. Not only is the foliage voluminous yet airy (mounds of feathery purple-black leaves), and its umbelliferous white flowers abundant, but A ‘Ravenswing’ will tolerate a little shade and a lot of sun. Plant now, or grow from seed. chilternseeds.co.uk
Viola riviniana (Purpurea group)
Another wonderful ground cover plan, this purple dog violet is as versatile as it is striking. At the Garden Museum I grow it alone in a small terracotta pot; at home it runs around on spreading stolons – much like a strawberry plant – gracing dimly lit corners with its heart-shaped leaves. dorsetperennials.co.uk
Summer
Dahlia ‘Bishop of York’
The ‘Bishop’ series dahlias all have the darkest of leaves and stems, so choose according to preferred flower colour. I find the yellow D ‘Bishop of York’ irresistible, but you might favour the scarlet ‘Bishop of Llandaff’, or the pink-blushed white ‘Bishop of Dover’. Order tubers in the next couple of months and pot up in March. Great flowers for cutting, fantastic foliage for contrasting. riversidebulbs.co.uk
Lobelia ‘Russian Princess’
Lobelias are excellent for damper, heavier soils, and much like long-serving Lobelia cardinalis, L ‘Russian Princess’ has wonderfully moody, deep purple eaves and striking magenta flowers. Grow alongside meadowsweet (Filipendula) and the tall oat grass Chasmanthium latifolium, and mulch in winter with a good layer of organic matter. barnsdalegardens.co.uk
Japanese parsley (f atropurpurea)
This ruby-tinged form of Cryptotaenia japonica is a clumping perennial suited to most soils. With its distinctive three-lobed leaves, it draws the eye with tones of plum, aubergine and dark purple. Pink flowers appear in midsummer, but play second fiddle to the rich leaf colour. Best interspersed among perennials, planted in multiples. bethchatto.co.uk
White snakeroot Although the white, pollinator-friendly flowers of Ageratina altissima ‘Chocolate’ arrive in late summer, the metre-high foliage is an unparalleled filler, sitting neatly among tall perennials. Grow this mid-border plant in full sun or semi-shade, alongside echinacea, cosmos and silvery artemisia. hardysplants.co.uk
Late summer/autumn
Ligularia dentata ‘Midnight Lady’
Another damp-loving perennial, this yellow daisy has large, dark, lily pad-like leaves that appear almost bronze in sunlight. This is a great plant for pots, where a surrounding layer of grit will deter slugs. Foliage can spread to around a metre; cut back flower stems to ground level after they’ve bloomed. barnesnurseries.co.uk
Calico aster ‘Lady in Black’
Rarely for an aster, Symphyotrichum lateriflorum ‘Lady in Black’ has attractive purple-brown leaves, rising long in advance of its pink and white flowers. As with all lofty, late-flowering North American asters, ‘Lady in Black’ is tolerant of almost all soil types and partners beautifully with ornamental grasses. Divide in spring to check its tendency to spread. hardysplants.co.uk
Actaea simplex ‘James Compton’
No list of dark-foliage plants is complete without at least one of the many magnificent Actaea cultivars. Closing the season with their slender, bottle-brush flowers, actaea’s foliage is worth all the effort of providing a fertile, organic-matter fed soil: tall, architectural and endlessly elegant. Plant the notably sturdy A ‘James Compton’ alongside other back border reliables such as Bistorta amplexicaulis and white veronicastrum. bethchatto.co.uk
