Cornus have been a mainstay at RHS Garden Rosemoor in Devon since Lady Anne Berry started a collection in the 1960s and 70s. With many more species and cultivars added since, it was one of the first to be given National Plant Collection status in 1982.
RHS Rosemoor’s National Plant Collection of Cornus (excl C. florida) covers 25 species and 85 cultivars, and it was originally begun by the late Lady Anne Berry who gifted Rosemoor to the RHS in 1988. She was a keen plants woman and collector, especially of trees and shrubs, and served as a member of the RHS Woody Plants Committee due to her knowledge.
Collection overview
All the dogwoods in the collection come from countries with similar climates to the southwest so are well suited to the conditions at RHS Rosemoor. Cornus kousa originates from China, Korea and Japan. It includes some wild-collected species but the majority are named forms that have been selected to provide a range of different growth habits or flower colour. In the Forest Garden, there is a small selection of Cornus mas (Cornelian cherry), a shrub from Europe with edible fruits that have the taste of a plum when fully ripe.
Best time to see them
The collection contains two main groups: winter stem colour dogwoods and flowering dogwoods. The stem dogwoods’ main season of display is from autumn to spring (October – March) when their bare stems are revealed in bright red, orange, yellow or acid greens. The flowering dogwoods are mainly Cornus kousa cultivars and these peak in late May to June, with fruits later in the summer. Many have good autumn leaf colour, too.
“They’re spread across the whole garden – as we have many different themed garden rooms. We can select cultivars with the right growth habit, stem colour or flower colour to suit various planting combinations. A lot of the stem dogwoods are focused in our Winter Garden and around the Lake to give that dramatic hit of vibrant colour in winter,” says Jonathan.
Winter stem colour
The collection continues to grow, in particular adding more to the redesigned and extended Winter Garden to provide a showcase of dogwoods as a key plant for the winter landscape. “Cornus alba Miracle (‘Verpaalen2’) is one we’ve selected for the new Winter Garden – it has a winter framework of red stems but interesting foliage too: tinged pink as it emerges in spring and then fading to cream and green variegations as the season progresses,” says Jonathan.
A classic combination to brighten winter days are the striking red stems of Cornus alba ‘Sibirica’ with the more subtle green to yellow of Cornus sericea ‘Flaviramea’ AGM. A cultivar Jonathan recommends both for good winter and summer interest is Cornus alba ‘Aurea’ AGM with a red stem in winter but beautiful golden leaves throughout summer, which works well in RHS Rosemoor’s Hot Garden scheme.
Not just for winter
The collection of flowering Cornus kousa offers a good representation of older and new selections that are considered to be among the best available. With such a wide selection to see, gardeners can choose one suitable for their garden size, from dwarf or tumbling forms to tall trees.
“Sadly we don’t have the space to grow all the Cornus kousa cultivars that are available, so we have ones that have been grown here since Lady Anne’s days and then I have added in ones I like or feel are really good selections such as Cornus kousa ‘Cappuccino’ AGM, which is a relatively new cultivar distinct from anything else around and recently received an Award of Garden Merit,” says Jonathan.
One that Jonathan feels should be grown more widely is Cornus kousa ‘Rosemoor Pink’. “I’m a bit biased perhaps but this was an original from Lady Anne’s collection that had been noted by experts as being quite different and unique. Several years ago, we named it after Rosemoor. Its bracts are a lovely shade of vibrant pink that lasts for weeks, and its growth habit is layered rather than upright, which means you can enjoy the colour at a lower level; a great plant which several nurseries are now selling!”
“One of my favourite flowering dogwoods and a great selection for smaller spaces is Cornus kousa ‘Madame Butterfly’, a spreading shrub that in early summer is adorned with white to cream bracts, followed by a mass of strawberry-like fruits that often weigh down the branches.”
Notes on cultivation