The Most Expensive Flower Book Ever Made: Thornton’s Temple of Flora
How a Georgian physician bankrupted himself trying to create the most beautiful botanical book the world had ever seen — and why it remains one of the greatest achievements in the history of illustrated natural history
There is a particular kind of ambition that does not calculate risk. It sees a vision so clearly, so completely, that the practical obstacles — the cost, the time, the likelihood of failure — simply fail to register with the force they should. Robert John Thornton had this kind of ambition. A physician by training, a botanist by passion, and an impresario by temperament, he spent the better part of a decade and the whole of his personal fortune producing a work that he believed would be the definitive celebration of the plant kingdom: The Temple of Flora, published in parts between 1799 and 1807.
It was, by any measure, an extraordinary achievement. It was also a financial catastrophe that haunted Thornton for the rest of his life. And it remains, more than two centuries later, one of the most visually spectacular books ever produced — a work in which botanical science and romantic art collide with an extravagance that has never quite been repeated.
Robert John Thornton and the Linnaean Dream
To understand The Temple of Flora, you need to understand the intellectual climate of late eighteenth-century Britain. Linnaeus had died in 1778, but his system of botanical classification — the sexual system, organizing plants by the number and arrangement of their stamens and pistils — had conquered European botany and was being enthusiastically adopted in Britain. Botanical illustration was at the height of its cultural prestige: the great voyages of exploration were returning with specimens from every corner of the globe, the Royal Botanic Gardens at Kew were expanding under the patronage of Joseph Banks, and the educated public had developed an appetite for natural history that expressed itself in collecting, in garden design, and in the purchase of illustrated botanical books.
Thornton conceived his project as a monument to Linnaeus and to the sexual system — a grand, multi-volume work that would illustrate the Linnaean classes with plates of unprecedented ambition and beauty. The full project was titled New Illustration of the Sexual System of Carolus von Linnaeus, and The Temple of Flora was its most spectacular component: a series of large-format plates depicting individual plants, each one set not against the plain white background conventional in botanical illustration, but against a dramatic landscape background that placed the plant in its natural or symbolic environment.
This was the innovation that made The Temple of Flora unlike anything that had come before. Thornton was not content with botanical accuracy alone. He wanted his plates to be works of art — to capture not just the morphology of the plant but its atmosphere, its emotional resonance, its place in the romantic imagination of the age.
The Mezzotint and the Romantic Landscape
To achieve this vision, Thornton commissioned some of the finest artists and engravers working in Britain at the time. The plates were produced using a variety of techniques — mezzotint, aquatint, stipple engraving, and combinations thereof — that allowed for a richness of tone and texture impossible to achieve with the line engraving conventional in botanical illustration. The results were unlike anything the genre had seen: plates in which the plant was rendered with botanical precision while the background dissolved into atmospheric landscape — stormy skies, moonlit lakes, mountain ranges, tropical shores.
The Pontic Rhododendron plate is among the most celebrated in the book. The plant — Rhododendron ponticum, native to the mountains of southern Europe and western Asia, introduced to British gardens in the mid-eighteenth century and by Thornton’s time already becoming the invasive presence it remains today — is depicted in full bloom, its clusters of pink and purple flowers rendered with the precision of a botanical diagram. Behind it, a dramatic landscape recedes into mist and shadow, with a yellow butterfly hovering at the margin between the botanical and the picturesque. It is a plate that belongs simultaneously to the tradition of scientific illustration and to the tradition of romantic landscape painting — and it is this double allegiance that gives it its peculiar power.
The technique of mezzotint — in which the engraver works from dark to light, burnishing a roughened copper plate to create areas of tone — was particularly suited to Thornton’s purposes. It allowed for the soft gradations of tone that romantic landscape required, the atmospheric effects of light and shadow that gave the backgrounds their depth and drama. Combined with hand-colouring applied by teams of skilled colourists, the finished plates had a richness and warmth that no purely linear technique could have achieved.
The Rhododendron: A Plant of Borders
The choice of the Pontic Rhododendron as a subject for one of the book’s most ambitious plates was not accidental. By 1800, Rhododendron ponticum occupied a peculiar position in the British botanical imagination. It had been introduced from the Iberian Peninsula and the Caucasus in the 1760s, and its spectacular flowering had made it an immediate favourite in the landscape gardens of the Georgian aristocracy. It was exotic enough to carry the glamour of the foreign and the distant, yet hardy enough to thrive in the British climate — a plant that seemed to embody the romantic ideal of the sublime made domestic.
There was also a scientific dimension to its appeal. The rhododendron belonged to Linnaeus’s class Decandria — ten stamens — and its complex floral structure made it a useful illustration of the sexual system’s principles. Thornton’s plate thus served a double purpose: it was a scientific document, illustrating the Linnaean classification, and a romantic image, evoking the mountain landscapes of the plant’s native range.
What Thornton could not have anticipated was the plant’s subsequent history in Britain. Released into the wild from the great estates where it had been planted as an ornamental, Rhododendron ponticum proved catastrophically invasive, spreading across heathlands, woodlands, and upland areas and suppressing the native vegetation beneath its dense canopy. The romantic exotic of 1807 is the ecological problem of today — a reminder that the relationship between the cultivated and the wild is never as stable as the garden wall suggests.
The Ruin of a Visionary
The Temple of Flora was published in parts, with subscribers paying in advance for each instalment. The production costs were enormous — the large format, the complex printing techniques, the hand-colouring, the paper — and Thornton had underestimated them catastrophically. Subscribers proved harder to retain than to acquire. The Napoleonic Wars disrupted the luxury book market. The project dragged on for years beyond its original schedule, consuming resources that Thornton did not have.
By the time the final plates were published in 1807, Thornton was financially ruined. He petitioned Parliament for relief, arguing that the work was a national cultural achievement that deserved public support. Parliament declined. He organized a lottery of the plates and the original copper engravings, hoping to recoup some of his losses. The lottery raised some funds but not enough. Thornton spent the remainder of his life in reduced circumstances, the great project that had consumed his middle years leaving him with little beyond the plates themselves and the knowledge that he had, against all odds, actually done what he had set out to do.
He had made the most beautiful botanical book the world had ever seen. It had cost him everything. And it endures.
A Book Out of Time
What makes The Temple of Flora so remarkable, two centuries after its publication, is precisely its excess — the sense that Thornton was attempting something that the conventions of his genre could not quite contain. Botanical illustration, at its most rigorous, is a discipline of restraint: the plant against the white ground, the morphological details rendered with clinical precision, the background eliminated so that nothing distracts from the scientific information. Thornton rejected this restraint entirely. He wanted his plants to live in the world, to be embedded in landscape and atmosphere, to carry emotional weight as well as scientific information.
This was, in the context of 1800, a radical proposition. And the result — those extraordinary plates in which rhododendrons bloom against stormy skies and water lilies float on moonlit lakes — remains radical today. There is nothing quite like The Temple of Flora in the history of botanical illustration, before or since. It is a work that could only have been made by someone who did not fully understand the risks he was taking, or who understood them and proceeded anyway.
That, perhaps, is the most romantic thing about it.
If the world of Georgian botanical art resonates with you, the Temple of Flora Rhododendron Journal brings Thornton’s 1807 Pontic Rhododendron plate to a hardcover journal — 150 lined pages, ready for botanical notes, garden observations, or whatever your days require.
References
- Thornton, R.J. New Illustration of the Sexual System of Carolus von Linnaeus. London, 1799–1807.
- Blunt, W. & Stearn, W.T. The Art of Botanical Illustration. Antique Collectors’ Club, 1994.
- Lack, H.W. Garden Eden: Masterpieces of Botanical Illustration. Taschen, 2008.
- Pavord, A. The Naming of Names: The Search for Order in the World of Plants. Bloomsbury, 2005.
- King, R. The Temple of Flora. New York Graphic Society, 1981.