This is no suburban allotment, however. The bees that work the borage flowers fly over from the Garrick Club's rooftop hives in Garrick Street, and you could practically lob a beefsteak tomato at one of the Charing Cross station commuters four storeys below. For this is the Coutts Skyline garden, on top of the bank's HQ in the Strand, and the violet French beans, kiwi fruits and other desirable edibles that crowd the narrow walkways are used in the company's restaurant kitchens one floor beneath, so going from plot to plate in a matter of moments.
"You get an extra vibrancy of colour and taste when you can pick produce fresh from your larder on the roof," says Coutts executive chef Peter Fiori, who grew tired, five years ago, of looking out of his fourth-floor office window and seeing a grey, unused space. He asked his great friend, the grower Richard Vine, who pioneered the micro herbs revolution at Le Manoir aux Quat'Saisons in Oxfordshire, to plant up a box of edibles, and presented it to the Coutts board, promising them that they would ultimately save on shopping bills by having their own market on the roof.
The board agreed and Vine got the prisoners at HMP High Down to knock up some planters from decking boards. With Vine tending the garden, Fiori's vision became reality.
Sadly, Vine died last year, but the garden and his legacy live on. Other restaurants with rooftops have followed suit, such as The Dairy, Clapham, where herbs are grown in supermarket crates, Pied à Terre in Charlotte Street and Kit Kemp's Ham Yard Hotel in Soho, where the raised beds sit between olive, apple and pear trees. The original, however, is arguably the best. Who else grows Douglas fir so they can bring a lemony zing to fish dishes by blending the needles with sea salt, or gets a kick — literally — by grating wasabi root pulled from a deep planter? "That thrilled the Japanese delegates," recalls Fiori, who stresses that the produce is here to eat, not to look beautiful.
However, these edibles are chosen for their on-the-plate good looks as well as their flavour. There are baby rainbow carrots, Black Truffle and Highland Burgundy Red potatoes, fragrant white as well as red alpine strawberries and russet mustard salad leaves with a horseradish tang.
Seeds are sown successionally, three times a year, so that there isn't one bountiful harvest, but continuous pickings. Everything is used — beetroot leaves are blackened in butter, courgette flowers are stuffed with crabmeat and aioli, French and English lavender, grown to pull in the pollenators, is used in ice cream, honey and biscuits, while the variegated leaves of nasturtiums, as well as their orange petals, add a peppery flourish.
The space — which warmed by heat from the walls of the building can reach over 40C — is used wisely. Each of the long walkways on four sides has its own garden. The sunniest side, at the front of the building, is for fruit, including tomatoes by the air-conditioning vents that whoosh warm air on to them. Runner beans, growing on tripods in big black buckets, are tucked into alcoves to protect them from winds, while vines twine around the handrails, grapes dangling invitingly.
There are other advantages of growing on high, says the Skyline's current gardener Jack Astbury, who created The Culpeper restaurant's rooftop kitchen garden in Spitalfields and was head grower at London's first commercial roof garden, above Budgens supermarket in Crouch End.
"There are no slugs and snails or damage from pigeons because the seagulls attack them," says Astbury, who has introduced new edibles to the garden such as Vietnamese coriander, which doesn't run to seed. He will soon be adding a wormery for the ultimate in composts.
"Otherwise the rules for growing up here are the same as any place where edibles are grown — fresh compost, watering, feeding. What stops people, I find, isn't the lack of space, it's a lack of imagination."
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