Jan Ravensberg: the grand old Dutch master of Irish horticulture

His Offaly-based nursery is the place gardeners go to find the rare, the unusual and the most garden-worthy trees and shrubs

Talk to anyone with an insider’s knowledge of the world of Irish horticulture and they will speak with an admiration verging on reverence of the work of the Dutch-born nurseryman Jan Ravensberg. A place where discerning plantspeople go to find the rare, the unusual and the most garden-worthy trees and shrubs, the wholesale nursery in Clara, Co Offaly, which he runs with his son Hans, has long been a mecca for garden designers, landscape architects and garden centre owners. Known as a master propagator who can coax almost any seed to germinate, any cuttings to root and with an almost uncanny ability to spot exceptional plants, this amiable Dutchman has spent his lifetime bewitched by the world of horticulture.

He is the sixth in a line of seven generations of nurserymen, and gardening is in his blood, a family tradition that he can trace right back to 1777. Ask him about his childhood growing up in Boskoop (the Dutch town famous for its dense concentration of nurseries) and he will tell you about how as a young boy he watched the sky fill with western Allies planes during the Berlin blockade in the late 1940s. How he built his first cold frame (a garden structure for protecting young cuttings and seedlings) out of the crashed remains of a Lancashire Bomber plane. How, at only 13 years old, he had to leave school when his father died to become the family’s main breadwinner but, determined to learn the nursery trade, he continued to work part-time with other nearby nurseries while completing his secondary school education by night. By the time he was just seventeen, the industrious teenaged Ravensberg had already established his own successful nursery business, testimony to a remarkable work ethic that’s always formed the backbone to his career.

It was in 1972 (exactly 50 years ago this month), that he, his young wife Siena and their two young children made what would be a life-changing move to Ireland, leaving behind their very orderly existence in the Netherlands for the relative wild west of rural Ireland in the early 1970s. At first, they settled in the Moyvalley area of Co Kildare, a part of the country now home to some of Ireland’s best plant nurseries, where Ravensberg got a job with Sap Nurseries. But within a few years he had struck out on his own, buying a centuries-old land steward’s house and several rolling acres in Clara, Co Offaly, where he soon established his own wholesale nursery.

Those early days of the business, Ravensberg remembers, were very different times. Essential materials for the smooth running of the business, such as grafting wax, containers, stock plants, even bamboo canes, all had to be shipped from the Netherlands and sometimes took months to arrive. “And then they might sometimes get stuck in customs for another month or so.”


Gardening was also only in its very infant stages in 1970s Ireland as regards garden-centre plants sales, while Irish garden centres themselves were generally small family-run businesses rather than the vast lifestyle stores that so many have subsequently become. Determined to open up the market, Ravensberg found himself in the position of introducing what were then uncommon species to garden centre owners and trying to convince them of their garden worthiness. “The plant knowledge wasn’t there, so it was a case of introducing new species and varieties and persuading them to give them a try.”

Ravensberg’s great gifts as a propagator and his near-forensic knowledge of shrubby plants and trees have stood him in great stead ever since, allowing him to propagate a wonderful range of plants with ease, from cuttings as well as by grafting, and from seed (a wide selection of wisteria varieties, for example, for which the nursery is well known). Very unusually for a modern Irish nursery (most buy in stock from abroad as young plug plants to then grow on), almost 90 per cent of the nursery’s stock is still propagated this way, allowing Ravensberg to cultivate what has become a distinctive palette of exceptionally garden-worthy plants.

“Jan has what I’d describe as this incredible, tenacious talent when it comes to seeking out great plants and propagating them,” says the plantsperson and Irish plant enthusiast Brendan Sayers. “That’s coupled with his encyclopedic knowledge of plants, something he shares so generously. Every time you visit his nursery, he’s growing something new that he wants to show you.”

One example is the ornamental tree known as Zelkova carpinifolia “Glasnevin”, named by Ravensberg after an especially handsome specimen that grows in the National Botanic Gardens in Glasnevin. He recently propagated it from cuttings taken from this tree, a horticultural feat achieved only once before in the history of the gardens.

The well-known Chelsea gold medal-winning garden designer Paul Martin is another great admirer of Ravensberg and his plants, as is the Cavan-based garden designer and consultant Daphne Levinge Shackleton. Both speak of the exceptional quality of Ravensberg’s plants. “I buy all my silver birch trees from Jan because the particular strain he grows is the very best there is,” says Martin (Ravensberg propagates all of the nursery’s stock of silver birch trees from grafted cuttings). “All the best Irish gardens, both private and public, are filled with wonderful plants that originally came from his nursery,” confirms Levinge Shackleton.

Seamus O’Brien, the brilliant head gardener of OPW-managed National Botanic Gardens in Kilmacurragh, Co Wicklow, echoes their words. “It’s no exaggeration to say that Jan is one of the great unsung heroes of European horticulture. In terms of exceptional nurseries that have provided so many outstanding plants to Irish gardens, he’s also part of a distinguished lineage that stretches back to Slieve Donard. One of his other defining qualities is his innate modesty. He’s never been someone to seek the limelight but as propagator and a connoisseur of plants, he can’t be bettered.”

This grand old man of Irish horticulture, a long-time member of the International Dendrology Society, is now 82, a time of life when many are already well into retirement. But not Ravensberg. “I get tired more easily these days,” he admits, his heavy Dutch accent still so distinctive that it’s amazing to think that he’s spent most of his life in the Irish midlands. “I can’t do what I once could. But I can still sit down at a bench and prepare hundreds of cuttings.”

Does he ever worry that his generation of nurserymen are a disappearing breed whose vast knowledge and rare range of skills are slowly but surely being lost? “I think that every generation produces plantspeople. So while things keep changing all the time in this business, those with a genuine deep interest will always find new ways to make it work. Each generation finds its own way.”

— Ravensberg Nurseries is strictly wholesale but its plants are stocked by most good Irish garden centres

Five great plants Jan Ravensberg has helped to introduce or maintain in cultivation

Crinodendron “Alf Robbins” A white-flowered, slow-growing variety of this normally scarlet-flowered, acid-loving, evergreen shrub with distinctively incised leaves that Ravensberg raised from seed of Crinodendron “Ada Hoffman”.

Cornus capitata “Kilmacurragh Rose” Named after the gardens of Kilmacurragh where it was first raised, this bushy, evergreen, acid-loving flowering shrub is prized for its decorative white-to-pink spring flowers and decorative summer fruits.

Taxus baccata “Summergold” A compact, mound-forming, resilient variety of golden yew that Ravensberg propagated from mother stock originally taken from his father’s nursery in the Netherlands

Eucryphia x intermedia “Rostrevor” Eucryphias are one of Ravensberg Nursery’s specialities and this particular variety is considered outstanding. A vigorous, acid-loving, evergreen flowering tree, its clusters of white flowers appear in late summer-autumn.

Berberis valdiviana: Hailing from Chile, this large, handsome, hardy evergreen shrub is known for its deep golden, drooping flower racemes which appear in spring and its glossy dark green foliage.

This week in the garden

Help to maintain soil fertility and soil health and protect soil from erosion by sowing a green manure in recently emptied vegetable beds. A range of green manures can be direct sowed into the ground at this time of year. Recommended seed stockists include fruithillfarm.com, quickcrop.ie and mrmiddleton.com

Order stock of spring flowering bulbs as soon as you can to make sure you have access to your favourite varieties. Recommended stockists include all good Irish garden centres as well as online specialist suppliers such as bulbs.ie and mrmiddleton.com, with the latter holding its much-anticipated annual Flower Bulb Open Day later this month (see below for details).

Dates for your Diary

Tuesday September 6th, Ballyknockan Farm, Castle Ellis, Co Wexford Y21A526, the Irish Dahlia Society’s National Show will take place, admission free. To submit an entry, please email Pat Thornton at tpatthornton@gmail.com or Trevor Stevenson at trevorandruth@gmail.com.

Saturday September 10th-Sunday September 25th, Mount Venus Nursery, Mutton Lane, Dublin 13 is holding its annual Autumn Plant Sale with a wide variety of plants discounted.

Saturday Sept 10th, 9am-5pm, Hall 6, RDS, Ballsbridge, Dublin 4 (Anglesea Road entrance), admission free, Mr Middleton’s annual Flower Bulb Open Day will take place with a huge selection of bulbs available including many new and unusual varieties. See mrmiddleton.com and rds.ie/getting-here for directions.

Fionnuala Fallon

Fionnuala Fallon

Fionnuala Fallon is an Irish Times contributor specialising in gardening