When the sun sets, some flowers come alive under the cover of darkness. We take a tour of the world’s most evocative nocturnal blooms. Jon White
Read more: “The night: The nocturnal journey of body and mind”
Giant water lily
(Victoria amazonica)
A true wonder of the plant kingdom, this water lily native to tropical South America is now displayed in show gardens worldwide. It is well known for its floating leaf pads that can grow up to 3 metres across and support the weight of a small child. But it's after dark that you may be rewarded with a spectacular floral display. On the first night of its bloom cycle, a single bud opens to reveal a white flower up to 45 centimetres across that emits a strong pineapple-like scent. What's more, it is up to 12 °C warmer than the surrounding air. The bright bloom, fragrance and heat attract scarab beetles, which crawl into the flower and feed on its nectar. As dawn approaches, the flower cools, its fragrance fades and it closes – trapping the pollen-covered beetles that fertilise it. When it reopens on the second evening, allowing the beetles to skitter away, it has turned deep pink. The flower then closes and sinks below the water, out of sight.
(Image: Sa Team/Foto Natura/Minden Pictures)
Night-flowering orchid
(Bulbophyllum nocturnum)
Of the 25,000 orchid species, this is the only one that blooms solely at night. The rarest specimen on our list was discovered in 2008 on the island of New Britain, Papua New Guinea, by Dutch botanist Ed de Vogel. It was a puzzle at first: the orchid's buds developed but seemed to wither without ever opening. It was only when de Vogel took one home overnight that he discovered its nocturnal glory: it bloomed at 10pm and closed at 10am. Because it is so rare, ideas about the flower need to be confirmed by more fieldwork, but botanists believe the flowering may be temperature-dependent, and that it is probably pollinated by a type of midge, attracted to dangling appendages that resemble tasty slime moulds. André Schuiteman, a senior orchid researcher at London's Royal Botanic Gardens, Kew, who co-wrote the orchid's formal description, says night-bloomers may have evolved fleeting flowers to prevent the theft of pollen or nectar by non-pollinating daytime visitors. This ephemeral beauty produces several flowers each year, but the blooms last for just one night.
(Image: André Schuiteman/Royal Botanical Gardens, Kew)
Queen of the night
(Selenicereus grandiflorus)
This climbing cactus is found in the deserts of Central America and the southern US, and is renowned for its beautiful, bat-friendly blooms that open around sundown and wither soon after sunrise. It is notoriously difficult to cultivate: horticulturalist Eli Biondi tends a single specimen at London's Royal Botanic Gardens, Kew, but has also seen them in the wild in Arizona. "The flower is pretty impressive," she says, although you may have to wait a long time to see one: the plants are often 20 years old before they flower. Even then, the chance is fleeting as the bloom closes and shrivels within hours. "That flower must be pollinated on that one night, which is why it is so showy," Biondi says. It has a powerful aroma too, that earned the plant the nickname "vanilla cactus". This scent, along with the stability provided by very long petals and sepals – tiny leaves just beneath the bloom – draws Mexican long-tongued bats and lesser long-nosed bats to it as a humid haven in the desert. The blooms can survive for a few hours after dawn, a chance to draw in daytime pollinators. "It's sort of a back-up plan," says Biondi.
(Image: Doug Wechsler/naturepl.com)
Midnight horror
(Oroxylum indicum)
"Botanically, it is the sole representative of its kind; aesthetically, it is monstrous." So botanist Edred Corner described it in his book Wayside Trees of Malaya. Not for the faint-hearted, this tropical tree found in parts of Asia could have sprung from the pages of an Edgar Allan Poe tale. It is also known as the broken bones plant, thanks to leaf stalks that, once they fall to the ground and dry out, eerily resemble human femurs. Most night blooms give off pleasant scents, but midnight horror's substantial flowers, which open just after sunset and close in the morning, give off a harsh odour. Fortunately for its survival, the stench appeals to pollinating bats. Buy some seeds on eBay – if you dare.
(Image: Fletcher & Bayliss/SPL)
Night-blooming jasmine
(Cestrum nocturnum)
This tropical evergreen shrub native to the West Indies was possibly introduced into Europe as early as the 1500s. It's not a true jasmine, but is so-named because of the pleasant, intense fragrance released by its smallish pale blooms when they open after dark. The aroma is said to be detectable miles away by pollinators – chiefly moths – and is reputedly the strongest scent of any flowering species. Even the relatively blunt human nose can detect its sweet whiff from 50 metres. Now grown in many gardens in sub-tropical regions, it's the easiest of this bunch to cultivate at home in cooler climates.
(Image: SergioTorresC/CC BY-SA 3.0) This article appeared in print under the headline "In the night garden"
