Going for gold
The cork oak is gaining popularity in British gardens, and not least at Chelsea.
Put a cork in it
“Cork is the new olive,” says designer Louise Cummins, standing in front of the wonderfully gnarled specimen in the Suber Garden (Silver Flora) she designed with Caroline De Lane Lea for the Chic small gardens category. “We liked it because it aged the garden a little bit - the rest of it is all very crisp and contemporary-looking, and I think it made it look more established.”
You can see the ancient lineage of the single Quercus suber (Cork Oak) that crouches over the garden in every wrinkle of its bark. It was once part of the ancient maquis, or scrub, surrounding the Mediterranean basin, and still covers nearly 6.7 million acres of land there.
But it’s also been quietly finding its way into gardens all over the UK. Cork oaks were first brought to Britain by gentleman botanists in the 17th and 18th century - giving them a longer history in this country than many more familiar Victorian imports.
They’re dotted all over the south, from the Chelsea Physic Garden in London to Antony, a National Trust garden above the Tamar Estuary in Plymouth - that one’s one of the biggest in the country. One of the oldest is the one in Painshill Park, Surrey, which has occupied its position on the top of a slope in the park for about 250 years.
“They grow well here,” says Mark Ebdon, head gardener at Painshill. “They don’t mind it hot and dry, and they don’t mind the frost.”
He describes the tree as a bit like a cross between an oak and an olive: like an oak tree, it’s open-growing, with a spreading habit. But its leaves are more like an olive’s, being slightly leathery and evergreen, and so is its wonderfully-textured, weathered-looking trunk.
There are 24 stockists of cork oak listed in the RHS plant finder, including one in Scotland, though Nigel Taylor, curator of the Royal Botanic Gardens at Kew, says they grow best in the south and south-west. Though they will tolerate some frost, he says, like many Mediterranean plants they won’t cope with cold and damp conditions.
“It’s catching on as a garden plant,” he adds. “It’s very architectural, and even the young ones have a character all their own.”
The corky bark which is its main attraction does take a while to form, even in its Mediterranean home, where cork producers leave trees to grow for 25-30 years before harvesting the bark. Harvesting actually stimulates the tree to produce more bark, thickening the corky layer and giving the tree its extraordinary texture.
Unfortunately, you can’t replicate that effect in this country, or harvest cork from cork oaks, since the trees don’t grow as quickly here and the bark can’t grow back thoroughly enough. But who knows what might happen with global warming; and just as we all have an olive on our patio these days, perhaps we’ll end up growing cork trees at the end of the garden, too.