Summer drought, winter floods? These plants will survive it all
Expert gardeners select the plants that have outperformed the rest in weather extremes
Anenomes in the garden. Photograph: Getty
It’s not easy being a plant growing in an Irish garden. Just consider the extremes of weather they have recently had to endure. Months of severe autumn and winter flooding that resulted in badly waterlogged soils, plus a series of fierce late frosts that badly seared young, soft growth, and squally early summer storms with winds so violent they stripped the leaves off trees and shrubs. And then – just to top it all off – a months-long near-drought right in the middle of a pandemic.
So which ornamental species have toughed it out and which have faltered? Which have proven their mettle and – rather than having an attack of the vapours and collapsing in a weakly wilting heap – have shown they can take a wet Irish winter, shake off a punishing hard frost and endure prolonged droughty conditions to emerge relatively unscathed. Because it’s these kinds of stalwart, no-fuss, let’s-just-get-on-with-it plants that we so badly need in our gardens as we face the increasing challenges of climate change.
Some, unsurprisingly, are species that Irish gardeners have often taken for granted in the past, the plants so doughty and ultra-reliable that we’ve blinded ourselves to their garden-worthiness or looked down upon them for their willingness to grow in the most unpromising of spots. Examples include lady’s mantle (Alchemilla mollis), the ultra-hardy perennial that forms a handsome mound of scalloped leaves from which a froth of lime-green flowers appear in early summer. Happy even in dry shade and in an impressively wide range of soils, it has proven itself impervious to winter flooding, late frosts and drought. Its only flaw – one I can readily forgive but others can’t – is its tendency to generously self-seed, a habit that can be easily controlled by timely deadheading.
In my own garden and flower farm, other tough, long-lived, obliging perennials that have stayed the pace this year include Japanese anemones, linaria, aconitum, Erigeron karvinskianus, acanthus, aquilegia, achillea, geum, bergenia, catmint, verbascum, Geranium macrorrhizum, foxgloves, astrantia, Stipa gigantea, liriope, echinops, alliums and the Welsh poppy (Meconopsis cambrica).
Those that have struggled to the point of collapse as a result of drought or late frosts or a combination of the two include hellebore, hosta, rodgersia, penstemon and ligularia, Shrubs and trees that proved resilient include Euphorbia wulfenii, hebe, birch, elder, hawthorn, amelanchier, Portuguese laurel and mountain ash. Those that were very badly burned by late frosts include cercidiphyllum, exochorda, beech and true ash (Fraxinus).
But what about other Irish gardeners stand-out plants of 2020? Here’s a fascinating little taster …
As the owners of Wexford-based Camolin Potting Shed, one of the country’s best-known specialist perennial nurseries, Susan and Gerry Harford have huge experience when it comes to selecting the varieties and species best suited to Ireland’s variable climate but even they agree that it’s been an exceptionally challenging growing year so far.
“It’s been really interesting to see the plants that have flourished and those that have struggled,” says Gerry. “Salvias in particular have done outstandingly well, especially the beautiful, inky-purple flowered Salvia ‘Amistad’ and the newly introduced magenta-mulberry pink Salvia ‘Amante’, a naturally occurring ‘sport’ of ‘Amistad’, both of which are very hardy and flower non-stop from June to October. Veronicastrums and sanguisorbas have also performed exceptionally for us this year as have our range of monardas including the mildew-resistant, scarlet-flowered Monarda ‘Jacob Kline’.
Robert Miller, the owner of Carlow-based Altamont Plants & Walled garden, one of Ireland’s loveliest, most atmospheric and best-stocked garden centres/nurseries, singles out roses as this year’s best performers. “Despite the very challenging conditions and near-drought, all of the roses growing in Altamont walled garden’s mixed borders have done very well this summer. But if I had to single out one variety, it would be Rosa ‘Dusky Maiden’, a repeat-flowering floribunda with large, deep scarlet, golden-eyed flowers that appear right throughout the summer and into early autumn. It’s just such a great plant and combines brilliantly with salvias and dahlias.
Finlay Colley, owner of Dublin-based Rare Plants Ireland, one of Ireland’s longest established specialist nurseries, singles out Gleditsia triacanthos f inermis ‘Sunburst’, the compact, thornless cultivar of the tree commonly known as the honey locust, as his star plant of 2020. “It’s been looking fabulous for months now.” This fast-growing deciduous medium-sized tree (eventual size of 12m x 10m) with very ornamental golden-yellow foliage is tolerant of pollution and enjoys a warm, sunny spot and a free-draining soil.
Cork-based plantsperson and nursery owner Hester Forde, whose garden Coosheen, outside Gounthaune, has featured in Gardens Illustrated, names the hardy, early-flowering mophead hydrangea, Hydrangea ‘Mirai’ as her plant of the year. “It’s a real eye catcher that has continued to look fabulous throughout the recent gales, drought and downpours, with rich red brown leaves in spring and striking coral-red flower heads that are flushed with white from June to October. I first saw it at the Garden House in Devon and instantly loved it.
As garden designers and co-owners of Mount Venus nursery in the foothills of the Dublin mountains, Liat and Oliver Schurmann have earned an international reputation as discerning plantspeople. Among their stand-out plants of 2020 is the ultra-long-lived, hardy, clump-forming, little-known perennial known as Valeriana alliariifolia, which has been in bloom from late May. “A glorious plant with umbels of pure-white flowers produced generously for many weeks, it’s a great, strong-growing perennial that’s happy in sun or semi-shade and has withstood the drought without any struggle,” says Oliver. “The same goes for any of the persicarias that we stock, all of which have coped admirably; Persicaria amplexicaulis var pendula, a selection from Crug Farm, is a particular favourite of ours with decoratively pendulous flower tassels in a shade of deep pink.”