Gardens: Dun Dubh rescue mission a great success

The formal garden overlooking Loch Ard. Picture: Ray Cox (rcoxgardenphotos.co.uk)

Four years ago Callum Pirnie, then head gardener at Crathes, the flagship NTS garden in Aberdeenshire, made a life-changing decision. He moved on from Crathes where he had spent 15 years restoring and developing the famous garden with more than 100,000 annual visitors and a staff of six, plus volunteers and trainees, and took on a new challenge at Dun Dubh in the Trossachs. This hidden late Victorian garden, west of Aberfoyle, had for decades been quietly disappearing into a sea of invading Rhododendron.

“The exceptional landscape sold me the job,” Callum says, standing on the terrace in front of the late Victorian house. “It is a spectacular setting.” Perched on the side of Dun Dubh hill, the house looks down the length of Loch Ard towards Ben Lomond, set against a framework of woodland and heather-covered hills. The six-acre site, Callum says, was a blank canvas. Substantial clearing of Rhododendron and regenerating trees had already been done to reveal the bones of an impressive, terraced Victorian garden complete with stands of majestic mature conifers, remnants of a formal 1920s rose garden, a kitchen garden and several other notable garden features surrounded by lawns running down to the loch.

“The restoration, development and upgrade of infrastructure could begin,” he says, with the enthusiasm that characterises everything he tackles in this garden. Drainage, critical on a site with an average rainfall of 60 inches “and increasing with climate change”, restoration and the rebuilding of derelict buildings, rebuilding of terrace walls, upgrade of main access paths, continued removal of Rhododendron and regeneration coppice to open up views, structural specimen tree planting and numerous other projects all occupied the first three years. Callum leads the way along the new Caithness stone-paved terrace with its southerly edging of pink Argyranthemum “Madeira Daisy” interspersed with purple Cordyline and southerly ribbon of lavender to the main garden.

A gravel path, which loops round the garden, leads first under a canopy of mature trees – the mature conifers form a key part of the structure and shelter at Dun Dubh – to a gap in the established yew hedge. From here a view opens up over a symmetrical, terraced, colour-themed, semi-formal garden flowing down to the loch. Geranium ‘Rozanne’ creates a cascade of blue over the lower wall, Hydrangea ‘Annabelle’ reflects the morning sun, drifts of Inula hookeri and Solidago ‘Queenie’ give explosions of gold, while occasional plantings of maroon-leaved Cotinus add structure.

The path continues to the kitchen garden where the focal point is the impressive new, Victorian-style glasshouse, tucked into the slope on the side of the hill. Here, on wet days, Callum tends peaches, grapes, tomatoes and cucumber, and a staged display of bright pink and blood red Pelargonium. Below, a huge restoration project resulted in the 10-foot retaining walls being rebuilt, raised beds being laid out on either side of a central path with its flight of original steps that lead under a rustic metal pergola planted with roses, honeysuckle and clematis.

Explaining that the uneven gradient of the steep slope presented unique challenges when it came to rebuilding the walls and accommodating raised beds, Callum adds that 60 tons of fertile loam were brought in to ensure top quality fruit and vegetables could be grown once again for use in the house.

At this time of year the freshly coloured apples and pears in the orchard are a joy to see on your way down to the old boat house, complete with its jetty leading out to the sparkling water. Here, to the left, a few remaining Rhododendron ponticum cling to the exposed cliff face, and here and there a specimen conifer reinforces the Japanese theme that reveals itself in plantings of azaleas and acers.

This theme is particularly evident in the moss garden to the right of the boat house, where different mosses stretch out in a palette of emerald green clinging to the ice-grooved bedrock. The path turns in a circular movement along the lower walk, taking you past small plantings of maples – maples and conifers are Callum’s speciality – sorbus, betula, and other choice trees and shrubs, past a water meadow feature on a wet slope down to the shore where purple Lythrum contrasts with naturalised deep orange Crocosmia.

The glint in Callum’s eye is a hint that another surprise is in store and the reason why he didn’t dwell on the cascade of plants that tumble down below the main terrace at the front of the house becomes clear. In front of us, assembled from 200 tons of weathered sandstone using individual stones of up to five tonnes, the newly developed lower crag and rock garden rises up impressively to nearly 20ft at the south west corner where a symbolic dry waterfall cascades on to a bed of rounded paddle stones.

Here a view opens across the loch to a dramatic cliff giving a classic example of ‘borrowed landscape’. Reinforcing the Japanese theme is the mature Pinus parviflora, pruned in the Japanese style, which is the crowning glory of this spectacular construction.

Climbing back up the slope to the west of the house there is one last surprise, assuming you have already explored the renovated buildings and garden above the main house, and the woodlands with their 140ft tall conifers to the north west. Here, the old ash tennis court site, the only flat space in the garden, has been redeveloped. A Tsuga “Western Hemlock” hedge screens the west edge and, to the east, the bank below the house overlooking the formal lawn has been re-landscaped to give three levels with ornamental drystone walls providing a striking structural backbone. A new heather garden including dwarf conifers and specimen Japanese Maples will give year-round interest while below, at lawn level, set against a six-foot drystone wall, is the formal 35-yard herbaceous border. It is primarily a late summer border, and includes Buddleias and Hydrangea paniculata varieties as structural plantings.

Here the autumn yellows and golds of Inula racemosa combined, Rudbeckia and Heleniums contrast with pale blue, late-flowering Aconitums and a soft palette of phlox varieties. In creating these sections, Callum drew on his experience at Crathes, choosing long-flowering plants known for their reliability.

Callum attributes the success of this huge project in part to an excellent working relationship with his employer who, despite often being away on business overseas, is supportive and engaged with every aspect of the work. “He also demands quality, and this sets the standard for all the hard landscaping carried out by a skilled team of Scottish craftsmen,” says Callum. Judging by Callum’s ever-present smile, the endeavour is a joy. “Where else would you get a setting like this to create an inspirational garden?”

• Dun Dubh, Aberfoyle, Stirlingshire will be open for the first time on 18 May and 14 September, 2014, contact Callum Pirnie ([email protected])