Pathless Forest by Chris Thorogood review – love letter to a monstrous flower

<span>The Rafflesia mimics the odour and appearance of rotting flesh.</span><span>Photograph: Anadolu Agency/Getty Images</span>
The Rafflesia mimics the odour and appearance of rotting flesh.Photograph: Anadolu Agency/Getty Images

If you think of flowers as beautiful, fragrant, decorous and domesticated – something you order from an online florist or pick up at your local garden centre – Chris Thorogood’s Pathless Forest should come with a health warning. It’s a love letter to the largest flowers in the world: the monstrous blooms of the 40-odd species – no one knows quite how many exist, or may have already been driven to extinction – of Rafflesia. This stinking, sprawling “corpse flower” grows in the tropical rainforests of Malaysia, Thailand, Indonesia and the Philippines, and from its nickname on, nothing about it is pretty. It’s a parasite that mimics the odour and appearance of rotting flesh to attract its favoured carrion fly pollinators, with a bouquet featuring notes of “blocked drains”, “sewage”, “pigs’ shit” and “bad chicken”.

It’s also the lifelong love of Thorogood, a botanist and academic who admits to a relationship with Rafflesia that echoes the monomania of any Werner Herzog antihero. “Dragged helplessly to heaven through hell and back, he became half-sick with his obsession to find it,” he writes of himself; like its subject, his prose is undemure, supersized, unbound by convention. The story starts with Thorogood as a plant-bewitched child, modelling Rafflesia blooms from papier-mache in an overgrown cemetery behind his family home. (He’s also a botanical artist with a popular Instagram account, and Pathless Forest is illustrated with his own detailed, atmospheric drawings and paintings of expedition colleagues, rainforest plants – and Rafflesia in all its liver-coloured, white-splotched glory.)

Several degrees later, Thorogood is now deputy director of the 400-year-old Oxford Botanic Garden. Like Britain’s other great scientific gardens, from Kew to Cambridge and Edinburgh, it flourished under an empire that drew much of its wealth from colonial cash crops: cotton, spices, tea, coffee, sugar, tobacco, indigo, opium. For the “plant hunters” of this age, botanical knowledge was inextricably linked with imperial conquest. Rafflesia itself is named after the British colonial administrator Stamford Raffles, who saw it flower in Bengkulu, Indonesia in 1818, the year before he established the trading post that would become Singapore.

But, unlike more tractable plant trophies, it has since refused to be cultivated in botanic gardens or even successfully stored in seed banks; the only institution in the world that has managed to coax it into bloom by grafting it on to a host vine is Bogor Botanical Gardens, near Jakarta. With more than 90% of forest cover lost in the Philippines alone, its dependence on its original habitat has left Rafflesia at severe risk of extinction – a ticking clock that propels Thorogood’s race to help document it in the wild and learn the secrets of its propagation.

In this overwhelming, densely woven setting, the boundaries between person, plant and environment start to dissolve

The journey transports him from the orderly glasshouses, lily ponds and walled gardens of his Oxford base into the titular pathless forests of Rafflesia’s range. This is a world of plants on the loose – Thorogood describes a dizzying profusion of species as he pushes through undergrowth, scrambles up mountainsides, and wades rivers with local researchers and guides. Birds and animals barely get a mention except as pollinators or antagonists (step forward Sunda porcupines and Java mouse-deer, which cause much botanist heartbreak by gnawing on Rafflesia blooms). These forests aren’t the familiar backdrop of nature documentaries; here, they’re the stars.

In this overwhelming, densely woven setting, the boundaries between person, plant and environment start to dissolve, along with old assumptions about what plants are. “I’m starting to think like the forest,” Thorogood writes. At intervals, his book takes on the voice of Rafflesia itself: wily, patient, bent on survival. The plant pushes up against the margins of scientific knowledge: though its blooms can be a metre across, Rafflesia spends most of its life as a microscopic thread within the tissues of a host vine, behaving, as Thorogood’s research with Harvard colleagues has shown, much like fungi, neither plant nor animal.

The experts here are not western academics – Thorogood admits that “at times I can barely name a single plant” in the forest – but the local scholars, foresters and indigenous guides who lead the way to Rafflesia’s home. The book’s hero turns out to be the elderly, unassuming Mr Ngatari, the “wizard” of Bogor who holds the secret to successfully propagating the plant, and therefore securing its future. Pathless Forest closes with Thorogood and Filipino colleagues poring over his cryptic instructions, and praying over their own grafted vine. Whether or not a foul-smelling, magnificent Rafflesia eventually blooms, this is a gripping, Technicolor account of why their efforts matter.

• Pathless Forest: The Quest to Save the World’s Largest Flowers by Chris Thorogood is published by Penguin (£25). To support the Guardian and Observer order your copy at Delivery charges may apply.