Matthew Biggs discovers how garden designers use foxgloves in their schemes
Most digitalis are short-lived perennials, whose lifespan (usually three to four years) varies according to the growing conditions – the only biennial is Digitalis purpurea. They are found in a range of habitats from woodland clearings to subalpine meadows, or, in the case of Digitalis parviflora (renowned for its slender spikes of chocolate coloured flowers) on dry stony habitats in sunshine.
Many prefer moisture-retentive, free-draining soil in sun or part shade and flower from early to mid-summer. They are dependable plants, whose status as favourites in styles from traditional cottage gardens to contemporary perennial plantings was endorsed by William Robinson, and confirmed by Piet Oudolf and others. The natural elegance of all the cultivated species can be used to add lightness, romance or architecture, depending on the scheme.
“I value them because they have a strong form,” says award-winning designer Amanda Patton MSGD, “without taking up too much visual weight within a planting – particularly Digitalis purpurea f. albiflora, which adds both light and height. I like to play with tones in woodland plantings, so use them a lot, sometimes with birches like Betula utilis var. jacquemontii and Geranium phaeum ‘Album’ for a green-and-white scheme; or Betula nigra with its dark stems and Japanese anemones Anemone x hybrida ‘Honorine Jobert’. It is a lovely mix under the birches or with Cornus alba ‘Elegantissima’.
“My style is to use big swathes of perennials so I sometimes intersperse them randomly within a structured framework of plants such as Helleborus niger, Geranium sanguineum ‘Album’, Liriope muscari, Paeonia lactiflora ‘White Wings’ and Hakonechloa macra. They are only in small clumps of three to five, perhaps with one or two together, dropped randomly into the design to create a rhythm.”
One feature of digitalis is that despite their short lifespan – perennials only last up to four years – many self-seed freely, adding dynamism, so the planting scheme changes annually. “To maintain the effect, I tend to use a combination of replanting and editing out self-sown seedlings that are in the wrong place.”
Amanda uses Digitalis lutea when she doesn’t want anything as strongly structural as Digitalis purpurea f. albiflora. “It adds a delicate lightness to a plant association and looks fantastic with Milium effusum ‘Aureum’, Tellima grandiflora and ferns such as the wonderfully textural Polystichum munitum.” Rockeries are coming back into fashion, often almost a scree, and species are ideal – D. grandiflora, D. parviflora (which flowers for a long time and is reliably perennial) and D. lutea all provide verticality without staking.
Perennial foxgloves are particularly at home among New Perennial planting. Evergreen Digitalis ferruginea reaches 1.8m, and has rosettes of dark-green leaves and attractive honey-brown flowers, which are densely packed along the stem, exuding elegance and sophistication. “They look striking planted through soft grasses such as Stipa tenuissima and against dark-red Persicaria amplexicaulis ‘Blackfield’, and they have a strong architectural form in winter, frosted and festooned with spider webs,” Amanda says.
“I have occasionally used Digitalis lanata, with its prominent white lip, as an interesting alternative to foxtail lilies. I’ve planted it with Molinia caerulea subsp. caerulea ‘Heidebraut’, but it would look good with Deschampsia cespitosa too.”
There is no doubt that the versatility and elegance of foxgloves will maintain their popularity in garden design, no matter how tastes change in the future.