Bittersweet vines, a smothering menace of unsuspecting American gardens and woodland edges, has a cousin at Oxford University. Celastrus orbicalutus has been adding medieval atmosphere to the hallowed quads of Magdalen College for many years. They are referred to by head gardener Claire Shepherd as “monsters,” their gothic shapes enhanced through creative cloud pruning. Let’s walk on the grass (when no one’s looking) and take a closer look at these strange creatures: Photography by Jim Powell, for Gardenista.
Oriental bittersweet, as Celastrus orbicalutus is also known, can grow to 40 feet and seems an odd choice for covering walls which don’t necessarily need to be covered. They are shown here in April this year, each gnarled branch ending in a goblet shape.
Like many gardeners who find employment in one of the Oxford colleges, Claire Shepherd has been at Magdalen for decades. Before she became head gardener 20 years ago, she had spent 10 years as an under-gardener, with plenty of time to size up the walls. “There were a few very old hydrangeas that had become heavy and boxy as well as the Celastrus orbiculatus that were overgrown and all over the place,” Claire says. “The Celastrus was one of the first to be dealt with. I took a long hard look at what there was to work with and set to work with secateurs,” she continues. “Creative cloud pruning was the answer to these monsters.”
Claire took her cue from the style of another notoriously chaotic shrub which had been tamed successfully at Magdalen, allowing the Oxfordshire stone to shine through. “The Chaenomeles speciosa (Japanese quince, shown here) had already been trained into cup shapes,” she says. “The wall shrub training has developed as time has gone by, as each shrub has needed to be either removed or drastically restyled.”
Fanned out against a wall between two windows, the roses are an unusual choice as well. Described as “bushy” by the Royal Horticultural Society (along with Japanese quince) Rosa Indigofera himalayensis ‘Silk Road’ has been trained in a fan shape to avoid a tangle. This is easy to do, by cutting out the oldest stems every few years and arranging the vigorous new shoots in an orderly manner.
The well-behaved (and long-flowering) ‘New Dawn’ climbing rose is used between the gothic shapes at Magdalen. “This rose tends to survive the north facing conditions,” says Claire. It is a heavenly shell pink.
With its pink-tipped foliage, Actinidia kolomikta is another vigorous climber (reaching 26 feet potentially) that is not allowed to consume the carved stone in the quad facing the New Buildings. Twining stems are kept untwined with vigilance when the shrub is young. Once a growing pattern is established, it is quite simple to maintain a shape.
The leaves are small and holly-like, similar to holm oak, and when left alone Garrya elliptica produces long tassels in winter. It is another bushy climber that allows itself to be manipulated in a Japanese-medieval manner. Jasmine can also be pruned selectively by cutting out non-flowering shoots and training it into a skeletal shape.
“I don’t purposely choose plants to experiment with,” says head gardener Claire Shepherd. “It’s more to do with whether I can visualize a shape or style that would suit the plant and its position.” For more pruning tips, see: