hen the director and artist Derek Jarman began making his garden on the great shingle expanse outside his cottage in Dungeness, local fishermen feared something occult was afoot. “People thought I was building a garden for magical purposes,” Jarman said at the time, “a white witch out to get the nuclear power station.” It’s not hard to see why. Approaching the black-tarred silhouette of Prospect Cottage, as you crunch your way across the otherworldly shingle desert on the tip of the Kent coast, you encounter a series of enigmatic stone circles bursting with red and yellow poppies. Driftwood totems rise above shaggy tufts of sea kale, while talismanic strings of pebbles dangle from rusting iron posts, above the metal balls of fishing floats emerging from clumps of gorse. The boxy hulk of a nuclear power station looms in the background, emitting a distant hum. It is one of the strangest, most magical garden scenes in the world – made no less so, back in the 90s, by the sight of Jarman in a hooded djellaba, pottering about among the blooms. In spite of the coronavirus lockdown, a little bit of the magic has now been transposed to the Garden Museum in south London, where a fragment of the late film-maker’s cottage has been recreated, along with some of his tools, artworks and excerpts from his films. The little museum, housed in a beautifully converted 14th-century church next to Lambeth Palace, is one of the first to reopen in the capital, with timed bookings limited to six visitors every half-hour, and hand sanitiser on tap. The nervy feeling of being out and about in public, mingling with gallery-going strangers for the first time in months, only heightens the hallowed aura of what’s on show. Jarman was one of the most important artists and gay rights activists of his generation, making groundbreaking avant-garde films such as Sebastiane, Caravaggio and Jubilee that garnered plaudits for their unabashed homoerotic power. Since he died of an Aids-related illness in 1994, his cottage and garden have become a site of pilgrimage for art students, architects and garden designers, but the house has never been open to the public, which makes this exhibition all the more welcome. Those who have visited Dungeness will be familiar with the very un-English prospect of encountering a private garden without a fence. Regulations in the protected nature reserve mean that fences are mostly forbidden, so property boundaries remain blurred. As Jarman put it (giving the exhibition its title): “My garden’s boundaries are the horizon.” The result is an awkward ballet of curiosity and deference: nosey visitors gingerly wander among Jarman’s plants and driftwood sculptures, gradually gravitating towards the cottage, without wanting to get too close, lest the net curtains start twitching. After his death, Jarman’s companion, Keith Collins, carefully maintained the property for 20 years, until his own death in 2018. After a period of uncertainty over its fate, the house and garden were saved for the nation in March this year, following a £3.5m crowdfunding campaign led by the Art Fund. Plans are in the works for a permanent public programme that will include residencies for artists, academics, writers, film-makers and gardeners, along with small tours by appointment. Until that time comes, prying eyes can be sated by the Garden Museum’s exhibition. Visitors enter the show through an antechamber lined with Dungeness shingle, where a panoramic photo mural of the landscape covers the walls and a solitary driftwood post emerges from the gravel, before entering a re-creation of the cottage’s hallway and study. Inside, a selection of Jarman’s energetic impasto paintings hang alongside bricolage works of found objects and a journal left open on the desk next to a little lead model of a house. A room next door shows clips from his films featuring the awesome Dungeness landscape, its huge skies and dramatic cloud formations recorded in flickering high speed on his Super 8 camera, along with scenes of the artist potting out his latest specimens and carefully arranging rocks into mystical circles. Since Jarman’s death, the garden itself has taken on a legendary quality, seeming to sprout in the barren landscape like a mirage, blooming from the beach against all the odds. As the exhibition explains, it wasn’t simply a case of choosing “the right plants for the right place”, but a calculated process of artifice – involving burying large quantities of compost beneath the shingle surface to make the plants appear to be growing from the pebbles. As every film-maker knows, a good deal of fakery is essential to the magic. Diagnosed with HIV in 1986, Jarman saw his Dungeness garden as an escape, crafted and nurtured in the face of his own impending mortality. Next to a planting plan in one of his sketchbooks are the scribbled words: “gardening on borrowed time”. As his friend, the photographer Howard Sooley, recalls in the exhibition catalogue, “for a time he cheated death hiding amongst the flowers and dancing with the bees”. Jarman bought the former fisherman’s cottage in 1987 for £32,000, using money left to him by his father, after he spotted it while filming on the beach with Tilda Swinton. He stripped the structure back to its bare bones, installed bright-yellow-framed windows and covered the outer walls with gallons of pitch black paint (a style that has since become the favoured vernacular for several designer pieds-à-plage that have sprung up along the beach. Obsessed with flowers since he was a boy, Jarman dreamed of a magical rose garden emerging from the arid shingle. His parents had given him the 1926 illustrated manual, Beautiful Flowers and How to Grow Them, for his fourth birthday, and he spent his youth making little gardens, winning a prize at boarding school for his plot. Prospect Cottage was the first time he had the chance to make an entire garden of his own from scratch, and he began with 30 rose plants, brought to the coast from a nursery in Kensington. As Collins wrote: “Derek imagined himself surrounded by a forest of impenetrable thorns, eventually hacked down by a true-hearted, handsome prince.” Most of the roses withered. Jarman turned instead to native plants – sea kale, wild peas, viper’s bugloss, teasels and sea holly. As Sooley recalls, he would use driftwood sticks to mark out the delicate purple shoots of the sea kale, “hidden under the shingle like long-abandoned land mines”. The sticks would then be adorned with with flotsam scavenged on his daily beach-combing walks, from chains and anchors to sea-smoothed bricks and sun-bleached crab shells. And so the garden grew, plants sprouting where the wind blew their seeds. Jarman occasionally intervened, writes Sooley, “waving dried seed heads over an area the might benefit from a foxglove or yellow horned poppy,” like some robed alchemist casting a spell, and marking out meandering paths “devised around the needs of plants, and not the other way around”. Despite the delay in opening, the lockdown has worked in the Garden Museum’s favour, to the extent that the exhibition is now more spread out than it would have been, rearranged with social distancing in mind. Stage designer Jeremy Herbert – who, like Jarman himself, has worked on sets for the English National Opera – has expanded the scenography beyond the usual exhibition space into the nave of the former church, with rustic benches and space for two of Jarman’s larger arresting canvases, daubed with the words Acid Rain and Oh Zone. A replica of a crucifix-like wooden navigation tower from the Dungeness beach looms over the whole scene, in a suitably Jarmanesque touch beneath the stained glass windows. This additional space has also allowed the inclusion of correspondence between Jarman and the celebrated garden designer, Beth Chatto, whose own gravel garden at Elmstead Market, near Colchester, has become a renowned international model for how to grow drought-tolerant species, the inspiration for countless gravel gardens, increasingly in vogue in these water-conscious times. Her inspiration? A chance visit to Prospect Cottage, and a hand-written list of recommended plants from Jarman himself – advising red and white valerian, sea campion, woody nightshade, Star of Bethlehem, scarlet pimpernel, cinquefoil, hound’s tongue, yellow rocket, hop trefoil and Nottingham catchfly, among others. As the film-maker said towards the end of his life: “Every flower is a triumph. I’ve had more fun from this place than I’ve had with anything else in my life. I should have been a gardener.” • My Garden’s Boundaries Are the Horizon is at the Garden Museum, London, until 20 September.