Glenwhan Gardens & Arboretum


Nr Stranraer

Dumfries and Galloway DG9 8PH


Seeing A Vision Come To Life

Not many people would stand on a windy hillside, looking out over an expanse of bogs, bracken and gorse, and think that it had the makings of a garden, but that’s what Tessa Knott-Sinclair did when she arrived at Glenwhan in the 1970s.

At that time, Knott-Sinclair had no experience of garden making, but she did have vision and energy and over the course of the last five decades she has made one of the most remarkable gardens in Scotland.

Glenwhan today is a sheltered enclave, filled with rare and unusual plants. Himalayan rhododendrons, trees from the Southern Hemisphere and all manner of beautiful flowers are packed into its 12 acres, including groves of Giant Gunnera from Brazil, native wildflowers and the Chinese magnolia vine (Schisandra rubriflora).

What keeps all of these plants flourishing is their suitability for Glenwhan’s acidic soil, combined with high rainfall levels and the benevolent effect of the Gulf Stream, which keeps frosts at bay.

Two small lochs, which were dug out by bulldozer and supplied by the overflow from the Georgian reservoir on the hillside above the garden, form a centrepiece. Covered in waterlilies and surrounded by aquatic-loving species, these have blended so successfully into their surroundings that it is hard to believe that they are man-made.

The paths that encircle them take visitors on winding trails through the garden, past banks of shrub roses and extensive plantings of hydrangeas, through groves of hollies and to meadows filled with wildflowers. An arboretum is filled with rare and exotic tree species, including the Chilean holly, Desfontainia spinosa, which produces tubular orange flowers in late summer and Araucaria imbricata, a variety of Monkey Puzzle tree that is under threat of extinction in the wild. A numbered tree trail identifies more than 130 different species that grow around the gardens, while a variety of different viewpoints take in the expansive horizon that stretches beyond Luce Bay to the Mull of Galloway and the Isle of Man.

Over the years the addition of a tea room, holiday accommodation and wedding marquee have encouraged visitors to linger and make the most of this exceptional location, which is at its very best in spring when the rhododendrons and azaleas are in flower and a sea of Candelabra primulas covers much of the garden in a rainbow of fondant colours.

Out Of The Blue

Bluebells are often a sign of ancient woodland and trees may once have flourished in the 17 acres of moorland that lie above the gardens but these have long since been replaced by coconut-scented yellow gorse bushes. In May, when both are in flower, the effect is spectacular. Yellowhammers dart amongst branches and bees, moths and butterflies come in large numbers. More than 120 different wildflowers have been recorded in this area and the adjacent reservoir is a haven for waterfowl of many kinds.

Raising Rhododendrons

In the early days, shelter from the prevailing winds was a priority, so Knott-Sinclair bought 100 hardy hybrid rhododendrons and planted them amongst the gorse bushes, which provided them with cover. As the rhododendrons grew, the gorse was cut away and then the real planting could begin. This was the introduction of species rhododendrons, which are more demanding of shelter and shade.

Glenwhan has more than 150 different species including Rhododendron macabeanum, the leaves of which can reach 30cm in length.

Streaming Service

The water gardens at Glenwhan extend all the way up the burn that serves the lochs. Several forms of Lysichiton have naturalised along the waterway and the native yellow flag iris grows in abundance. The boardwalk that crosses the stream allows visitors to immerse themselves in the lush foliage, which includes dense stands of Eupatorium which in summer are 2.5m tall.

Smart Salads

Vegetables are grown in a decorative potager, where edibles mix with annual flowers. Sweet peas scramble up canes, wooden obelisks support runner beans and herbs grow in the sunniest spots. Box and privet hedging has been used to divide the spaces and the addition of a bench makes this a tranquil spot.

Plants To Take Home

Glenwhan has a small nursery selling plants that have been raised from those growing in the garden. It can also grow to order, propagating from specified plants and shrubs.


The gardens are open daily, 10am-5pm. Tickets: £7.50/£6/free (under 7s)

Tel: 01581 400222