On a first or even a second glance, there’s nothing about the native plant colloquially known as yellow rattle (Rhinanthus minor) that seems in any way extraordinary. Typically found growing in grassy meadowlands, its short spikes of yellow flowers appear at this time of year, but are far less decorative than other showier natives such as the lofty foxglove, while even its dainty growth habit means that it’s easily overlooked.
But it’s what this plant is busily doing at root level, just beneath the soil surface, that makes it so very special, as was proved to me on a recent visit to the wonderful wildflower meadows of Kilmacurragh Botanic Gardens in Co Wicklow.
Nine years ago, when Séamus O’Brien, Kilmacurragh’s head gardener, gave himself the challenge of restoring its historic meadows back from tightly mown lawns to their original wild state, there were only a handful of yellow rattle plants growing in this OPW-managed garden.
But as someone who had regularly visited the meadows of Great Dixter in the UK and carefully studied its late owner Christopher Lloyd’s book on the subject, O’Brien knew that this diminutive wild annual was crucially important to the restoration of Kilmacurragh’s meadows.
That is because yellow rattle is what’s known as a hemiparasite. Beneath the ground it forms strange, root-like organs known as “haustorias” that rob water and nutrients from host plants – typically grasses – thereby reducing their vigour.
Species rich meadow
As an annual plant, it then sets seed in late summer before dying in late autumn, usefully leaving behind bare patches of soil that are colonised by other wildflowers as well as by yet more new yellow rattle plants the following spring. The result, over time, is a species-rich wild meadow alive with pollinating insects and birds, of the kind that older generations of Irish people remember with such fondness from their childhood.
In the early years of Kilmacurragh’s meadow project, O’Brien carefully harvested the yellow rattle’s ripe seed by hand in late summer, painstakingly sprinkling it onto tiny patches of bare soil that he had scratched to give it the best chance of germination. “It needs to be sown as really fresh seed, ideally sourced locally,” he says.
At that stage, the most predominant species found growing in Kilmacurragh’s seven acres of meadows was the tall, coarse, perennial native grass commonly known as Yorkshire Fog (Holcus lanatus), whose vigorous growth habit allows it to quickly crowd out most other wildflowers and less competitive grasses.
But as the yellow rattle gradually took hold, something magical began to happen. Slowly but surely the meadows’ population of Yorkshire Fog dwindled, while a host of dainty wildflowers and finer grasses took its place. Nine years later, there are over 130 flowering species in those same meadows, with individual communities of plants varying greatly in accordance with the particular soil and site conditions in which they’re growing. Almost all are native, with the addition of a small amount of decorative but non-native species that O’Brien has deliberately introduced as a form of artful but ecologically appropriate embellishment. “Kilmacurragh is what’s known as a Robinsonian garden [after Irish wildflower gardener William Robinson], so there’s a certain amount of licence in that regards,” he says.
Happy companionship
And so at this time of year, in the richer ground of Kilmacurragh’s top meadow, close to the gaunt ruins of its historic house, you’ll find native Irish wildflower species such as oxeye daisies, cat’s-ear, sorrel, red clover and the ubiquitous yellow rattle flowering in happy companionship with Lilium martagon and Astrantia major – both pretty, non-native perennials found growing in mountainous meadows of Europe. Earlier in the year, you’ll find other non-natives in flower including crocuses first planted by Kilmacurragh’s previous owners, the Acton family, as well as the graceful snake’s head fritillary, narcissus, and the starry-blue Camassia quamash, which O’Brien recommends as the very best species of Camassia for a meadow.
Meanwhile, in the thinner, less fertile, acid clay of Kilmacurragh’s lower meadows, the dainty native umbellifer known as pignut or “fairy potatoes” is flowering alongside sheets of yellow rattle and wild heath spotted-orchids, punctuated by sprinkles of tiny pink-flowered lousewort, bird’s-foot trefoil, ribwort and meadow vetchling. All these happily intermingle with many less vigorous native grasses, as befits a true wildflower meadow. The effect is theatrical yet curiously restful, intricate and yet wonderfully spare, a sort of soothing symphony where each species contributes a single but important note.
“The concept of a meadow can be a confusing one,” explains O’Brien. “In their mind’s eye, people often expect something that’s not at all grassy but very floriferous, or what’s properly called a ‘pictorial meadow’. Lovely as it is, that’s a very artificial creation, achieved by mass-sowing seed of a very carefully chosen combination of non-grassy plants. But with true grass meadows, like those at Kilmacurragh, it’s more a case of carefully editing what already exists by introducing certain key plants such as yellow rattle while also spot-eradicating a handful of thuggish species such as dock and thistle.
“Other than that, the only other thing we do is to cut the meadows right back once a year in the first week of September, after the plants have finished setting seed. It’s saved us many hours of tedious grass cutting, but it’s far more than that. There’s a bittersweet quality to Kilmacurragh’s meadows, which really resonates with visitors to the gardens. They remind us of what we’ve lost as a result of intensive agriculture and the use of artificial fertilisers and herbicides.”
This week in the garden
The recent heavy rainfall has brought slugs out in their droves, so it’s important to be extra vigilant to protect vulnerable seedlings and young plants. The most effective, organically friendly method of control is regular inspection of your flower/vegetable beds, as well as any seed trays or plant pots, with sharp scissors or secateurs in hand. Any slugs found munching precious plants can then be quickly dispatched by being snipped neatly in half and left for the birds to enjoy.
Keep regularly deadheading roses to ensure a longer display of flowers and tidier looking plants, using secateurs to snip off the individual faded blooms. If you grow David Austin English roses which flower in repeated flushes, you’ll need to summer-prune the plants after each flush of flowers has finished, cutting back the individual flowering stems to two to three sets of leaves.
Net young brassica plants now to prevent cabbage- white butterflies from laying their eggs on the undersides of leaves. Otherwise the butterfly’s larvae can do terrible damage to the plants. Young carrot seedlings should also be protected with garden fleece or a fine-gauge netting such as Bionet (available from Cork-based Fruithill Farm) to prevent carrot flies from laying their eggs into the base of the plant. The smell of the carrot plant attracts the fly, so always carefully and quickly dispose of any thinned seedlings.
Dates for your diary
Tomorrow ( June 19th) at 12pm Killruddery Gardens, in Bray, Co Wicklow, the British organic gardener Charles Dowding will give a talk on his ‘No-dig” approach to food growing. Tickets cost €7.50 (adult) and include entry to the gardens, see kilruddery.com Sunday, June 26th (10am-5pm), garden designer Arthur Shackleton will host an open day at his country garden, Fruitlawn, in Abbeyleix, Co Laois. Admission €5, see arthurshackleton.com Saturday 25th-Sunday 26th June (11am-5pm), Mount Stewart Garden Fair, Mount Stewart Gardens, Newtownards, Co Down, with stands by many visiting specialist nurseries, admission £7.72 (€9.75) includes entry to the gardens, see nationaltrust.org.uk
