How botanical gardens helped to establish the British Empire

Sydney’s botanic garden is a green jewel that lies alongside the city’s opera house. The plants (along with the opera lovers and the animals at the zoo) have access to “absolute waterfront”, the two words that set most Sydneysiders’ pulses rating. Yet the garden’s users – from the morning joggers to the Japanese brides and grooms getting their pictures taken – probably don’t realise that the garden helped found an empire. Without Sydney and gardens like it, the great Victorian botanical empire that centred on the Royal Botanic Gardens at Kew might never have existed, and without Kew, the British Empire itself would have been very different and probably much less influential.

In October 1812, the government of the colony of New South Wales (NSW) issued a proclamation that informed the people of Sydney that “the whole of the Government Domain” was being “completely enclosed by stone walls”. From that day forward, “no Cattle of any Description whatever” were permitted and any animals “found trespassing” would be impounded. The walls referred to are still visible within the garden, which trace their origin to this proclamation (although it was not formally founded until 1818).

NSW was, of course, a penal colony when the garden was founded and Sydney was a small, shabby town that faced repeated droughts and near famines. Everything from writing paper to seeds for the colony’s farms had to be brought over from Britain, a hazardous voyage that typically took six months. It can hardly have been obvious that the colony needed a botanic garden, yet Sydney was far from unique. St Vincent, in the West Indies, was the first colony to found such a garden (in 1765), and Britain’s East India Company decided it would be profitable to found one at Calcutta soon after (1787).

Eventually, there would be a network of gardens that spanned the globe, which would prove vital to the British Empire, allowing vital crops like rubber and cinchona (the tree from whose bark quinine was extracted) to be collected outside the empire and moved to colonies where they could be grown profitably. (Think about all those rubber trees that now form forests in southeast Asia; their scientific name is Hevea brasiliensis, meaning “from Brazil”.) However, during the years when most of the gardens were founded, grand imperial plant transfers were neither planned nor possible. So, why were they established?

The history of the Sydney botanic gardens, like that of NSW itself, is tightly connected to the history of Kew. In 1770, when Captain James Cook arrived on the east coast of the largely unknown Terra Australis, his ship’s botanist, the 27-year-old Joseph Banks, was so astonished by the variety of new plants that he named the site “Botany Bay”. After their return to Britain, Banks used his collections to turn himself into a scientific celebrity. He became Sir Joseph, friend and confidante of King George III, president of London’s Royal Society and one of the world’s most influential scientific men. In 1779, when the British government was looking for a new dumping ground for British convicts who were (understandably) no longer welcome in the former American colonies where they had previously been sent, Banks argued successfully that the land around Botany Bay was fertile enough to sustain a new convict settlement.

Without Sydney and gardens like it, the botanical empire that centred on Kew might never have existed

One the many pies Banks got his increasingly fat fingers into was the royal garden at Kew, which he and his friend the king saw as vital to preserving the nation. The key was improvement, enclosing common land to make it private, creating new owners with the incentive to drain, manure and tend it, increasing yields and profits. (And higher yields also meant full bellies that would stave off the threat of French-style revolution.) The same ideology was at work in Sydney. When the governor, Lachlan Macquarie, decided to put his surplus convicts to work by walling in the land, it was with a view to improving it, creating a entrepôt for badly needed agricultural seeds, which the garden’s first director bartered for rarities from Australia’s still-mysterious flora. The cones of the gloomy, enigmatic Banksia trees, for example, a genus named in honour of Banks himself, were much sought after by Europe’s botanists. In 1829, a plant collector called William Baxter thought his hard-won Banksia specimens valuable enough to risk a flogging by threatening to “knock down” anyone who tried to take them from him. Similarly, when the Calcutta gardens were founded, the East India Company hoped they would help them to break the Dutch spice monopoly.

In 1787, Banks hatched a scheme for improving the plantations in the West Indies. If a cheap, nutritious food source could be found, the cost of keeping the suffering slaves alive would fall and large-scale cotton cultivation could begin, feeding Lancashire’s mills and increasing exports to Asia. Everyone’s profits would rise, with no regard for the human cost. The task of transporting the chosen food, breadfruit, from the central Pacific was entrusted by Banks to William Bligh, captain of HMS Bounty. The voyage didn’t go quite as planned, but when the breadfruit finally arrived from Tahiti in 1793, they were planted in the botanic garden at St Vincent. Local plantation owners could then obtain cuttings to start growing it themselves. A similar scheme was tried at Sydney with grapevines that were grown in the gardens and then distributed freely in the hope of fostering a profitable industry that would help the colony pay its own way. The Kew-trained botanist Allan Cunningham, who briefly had charge of the gardens in the 1830s, also expressed the hope that producing good local wines would “tend to diminish the pernicious use of ardent spirits among the lower classes of the Colony”, thus adding “not a little to their comfort and happiness”.

Unlike the breadfruit scheme, Sydney’s vines had nothing to do with Kew. Banks had died in 1820 and the royal garden went into a decline that almost proved terminal. It was dirty and dilapidated and, in an effort to reduce plant thefts by local nurserymen, the superintendent had hit on the ingenious solution of removing the labels from the plants in the hope that would-be thieves would be unable to identify valuable rarities. (An innovation that severely reduced the garden’s usefulness to botanists.)

Gardens like Sydney responded by communicating directly with one another; any passing ship would be entrusted with a few plants or seeds and a letter, which were delivered free by enthusiastic captains to wherever they next called. The garden’s archives are full of letters from Mauritius and India, Cape Colony and Ceylon, but from 1820-40, Kew’s name is seldom mentioned.

Back in London, the government was (as ever) looking to cut public expenditure, and considered closing Kew. In 1838, the botanist John Lindley was asked to report on the plan, but instead of closure, he proposed the government should remove the garden from royal control and run it directly. His rationale was that there were already “many gardens in British Colonies and dependencies . . . in Calcutta, Bombay, Sahranpur, in the Isle of France [Mauritius], at Sydney, and in Trinidad, costing many thousands a year”. Yet, the value of these gardens “is very much diminished by the want of some system under which they can all be regulated and controlled”. Yet if proper co-ordination could be established, the empire’s gardens were “capable of conferring very important benefits upon commerce and . . . colonial prosperity”.

Lindley’s report was accepted but he was disappointed when the task of running the “new Kew” went to William Jackson Hooker, Glasgow’s professor of botany (who had been the intended recipient of Baxter’s Banksia cones). Hooker got the post because he had a better sense of the government’s priorities than Lindley; he was willing to work for a lower salary. Under Hooker and his son, Joseph, Kew would become the “great botanical exchange house for the empire” that Banks had envisaged.

Packets of seeds, cuttings of plants and dried flowers still flow into Kew’s collections from all over the world. Today, however, Kew is no longer at the centre of an empire, but a partner in a global network of gardens that are collaborating to record and protect the wealth of plants upon which virtually all life on this planet depends. Kew runs the Millennium Seed Bank, an international effort to preserve the seeds of as many plants as possible as insurance against future losses of genetic diversity. Yet without the unplanned, unco-ordinated efforts of men like Macquarie, Kew might not exist at all.

Dr Jim Endersby is reader in the history of science at the University of Sussex. He is the historical consultant to the new BBC Radio 4 series, “Plants: From Roots to Riches”, which began on Monday this week

Photographs: The Art Archive/Alamy; Bridgeman Images; Reinhard Schmid/4 Corners; Science Photo Library; Photocuisine/Alamy; H&J Eriksen/Nature Picture Library; Mary Evans/Natural History Museum; Vittorio Sciosia/4 Corners