In 1656, a young nobleman from the Dutch province of Utrecht, Hendrik Adriaan van Rheede tot Drakenstein, joined the Dutch East India Company (VOC) and set sail for the east. With a sword in hand and ambition in his heart, he quickly distinguished himself in Admiral Rijckloff van Goens’s brutal campaigns against the Portuguese across Ceylon and the Malabar coast. Like many 17th-century Dutch nobles, van Rheede was a quarrelsome subordinate. Yet his boldness on the battlefield earned him rapid promotions—first as sergeant major of Ceylon, then as commander of Malabar.
Though not formally trained in botany, van Rheede developed a deep fascination with the exotic flora he encountered beyond the Cape of Good Hope—in Batavia, Ceylon and, most strikingly, Malabar. To him, Malabar (the entire stretch of the Kerala coastline was then referred to as the “Malabar coast” by foreign traders) was a botanical treasure chest. He was captivated by the giant woody climbers and vast banyan trees—sacred to the Malabaris—that loomed like natural cathedrals over the land. Equally impressive were the Malabaris themselves, whose intimate knowledge of local flora allowed them to craft an astonishing array of herbal medicines in the ayurvedic tradition.
Unlike most colonial officers, van Rheede grew fond of the land and developed a close relationship with local rulers of Kerala such as the raja of Cochin. The fact that van Rheede had saved the life of the king’s mother during the 1662 battle in Fort Cochin likely strengthened their friendship.
Documenting the rich plant diversity of Malabar with the precision expected by European standards became an enduring passion for van Rheede. According to the late botanist H.Y. Mohan Ram, his motivation was not purely scientific—there was also a political dimension. Van Rheede believed Malabar was self-sufficient in both military and commercial terms and considered Cochin—captured by the Dutch from the Portuguese in 1663—a more strategic choice than Colombo for the VOC’s Southeast Asian headquarters.
It was within this context that he initiated the compilation of Hortus Malabaricus—a monumental work published between 1678 and 1693—that became the most comprehensive printed record of the natural wealth of Asia and the tropics during the colonial era.
Cut to 2009.
After a successful stint in the IT industry, where he founded California Software Co. Ltd (Calsoft), tech entrepreneur Sam Santhosh—later known as the “Genome Man of India”—took his first steps into genomics. He saw DNA sequencing as a horizontal technology capable of powering multiple companies across diverse sectors.
Through his Kochi-based incubator, SciGenom Labs, he launched his first venture, MedGenome. When he spun it off in 2013 with a new lab in Bengaluru, he simultaneously began incubating a second genomics company, AgriGenome, focused on sequencing plant genomes to improve crop varieties. That, he says, was a revelation.
“The genomes of plants showed me how much more complex they were compared to human and animal genomes,” he recalls. “This sparked a deeper interest in plants. Since Kerala is one of the world’s biodiversity hotspots, I began reading more about its flora—and that’s when I stumbled upon Hortus Malabaricus.”
Santhosh was awestruck by the wealth of knowledge in the 12-volume treatise. He longed to see a garden that brought to life all 742 plant species detailed in the work.
“While visiting botanical gardens across Kerala, I did come across sections on Hortus Malabaricus, but they were only partial collections,” he says.
During its compilation, van Rheede had faced numerous challenges—including dismissal as governor of Cochin, the untimely deaths of trusted botanists and a lack of funds for publication. Yet his perseverance, ingenuity and passion drove the project forward. Ever since reading about van Rheede, Santhosh has felt a deep urge to honour the Dutch governor who risked his career to undertake one of the most ambitious botanical documentation efforts of his time.
Motivated by this vision, Santhosh launched the Hortus Malabaricus Garden Project in 2016—a living biobank intended to support researchers studying the medicinal plants featured in the historic text. Earlier this year, the garden—spanning 27 acres and now housing over 1,800 plant species, including 730 of the 742 in Hortus Malabaricus—was opened to the public in Cheruthuruthy, in Kerala’s Thrissur district. Notably, this collection includes a significant number of plants endemic to the Western Ghats. Santhosh’s goal is to grow the collection to 5,000 species by 2030, predominantly from Kerala and the Western Ghats.
At the garden’s entrance stands a bust of van Rheede, placed beneath a mango tree adorned with a bamboo creeper endemic to the Andaman Islands. The garden is divided into 14 sectors, including dedicated sections for aquatic and prehistoric flora. The main pathway connecting these sectors—the garden’s central artery—is named after van Rheede.
Santhosh, who serves as strategic adviser to the Kerala Genome Data Centre—established to propel the state’s biotechnology sector—believes the garden will be of immense value to their work. It also features a taxonomy and biochemical lab, aimed at bridging the gap between traditional medicinal knowledge and modern genomic and soil microbiome research—connecting the wisdom of the ancient world with modern science.
Van Rheede himself had undertaken a similar act of bridging east and west when he initiated Hortus Malabaricus, combining indigenous knowledge with European scientific inquiry. To overcome the language gap, he founded a “Tolken School” (school for translators) in 1668 in the princely state of Thekkumkoor, with which the VOC had trade relations. The school was established in Kottayam, then the capital of Thekkumkoor, according to historian Rajeev Pallikonam.
“Herman Hasenkamp, a retired Dutch soldier and polyglot living in Kochi, was the first preceptor of this school,” Pallikonam notes. “Van Rheede wanted Hasenkamp to learn Sanskrit—perhaps because many ayurvedic medicinal texts were written in that language.”
According to Pallikonam, Latin, Dutch, Sanskrit and Malayalam were taught at this school, where Dutch VOC men, local Christians and Konkani Brahmins studied together. The school existed for a little more than a decade, and the Thekkumkoor king himself is said to have taught Sanskrit there.
Though short-lived, the school produced individuals who made vital contributions to Hortus Malabaricus.
“Herman van Donep, who graduated from this school with distinction and later became van Rheede’s secretary, was responsible for the Latin translation,” Pallikonam explains. “D. John Caesarius, who oversaw the school’s operations, also coordinated work on the project.”
Hortus Malabaricus documented not only the uses of plants but also their medicinal properties, including methods of preparation and application. A central figure in this effort was Itty Achuthan, an Ezhava physician from Malabar, who extracted ethnomedical knowledge from palm-leaf manuscripts for inclusion in the compilation. A major sector in the Hortus Malabaricus Garden is named in his honour.
Achuthan dictated the content in Malayalam, which was reviewed by three Konkani-speaking gymnosophist priest-physicians—Ranga Bhat, Vinayaka Pandit and Appu Bhat. The garden also pays tribute to these contributors.
Four Dutch soldiers created the illustrations, with van Rheede personally overseeing the descriptions. A panel of 15-16 physicians and botanists from across Malabar examined the compiled material and offered their insights into the curative potential of each plant.
Each plant’s description in Hortus Malabaricus includes details of its growth habit, leaves, flowers, fruits, colour, scent, taste and practical uses—all listed under their original Malayalam names. The illustration plates are inscribed in Roman, Malayalam and Arabic scripts, while Konkani names appear in Devanagari. Of the 791 plates, 712 are in double folio size and 79 in folio size. The original Malayalam text was translated into Portuguese, Dutch and Latin, and would not be available in Malayalam again for centuries.
It is believed that van Rheede employed over 200 local collectors to bring him plants—or twigs bearing flowers, fruits and seeds—across different seasons. Many of these eventually found their way into VOC gardens. Influential figures such as Stadtholder William III (later king of England) and several Dutch botanists requested van Rheede to send plant specimens from India, leading to the introduction of many unique Malabar species into European gardens.
While creating the Hortus Malabaricus Garden, Santhosh’s team of naturalists had to venture beyond the region historically identified by the Dutch as Malabar to locate some of the rare species mentioned in the text.
If it took van Rheede one and a half decades to complete Hortus Malabaricus, it took acclaimed botanist K.S. Manilal three and a half decades of intense labour to translate its 6,000 Latin pages into both English and Malayalam with exceptional fidelity. His work made the historic treatise accessible to a wider community of scholars and plant enthusiasts.
Manilal also played a pivotal role in reviving knowledge about the immense biological value of south Indian herbs. He identified and collected specimens of most plants documented in Hortus Malabaricus, preserving them in a dedicated herbarium at Calicut University.
“The Hortus Malabaricus Garden is a tribute to Manilal as well,” says Santhosh, who is currently working on a comic book about Hortus Malabaricus—an artistic homage from his end.
Santhosh’s garden also incorporates historical and archaeological motifs from five distinct periods of Indian civilisation. “I’ve always been fascinated by history and archaeology, and I make it a point to visit as many archaeological sites and museums as possible,” he says. “The idea of organising a section of our garden to reflect five major Indian civilisations, starting from the Harappan era, was inspired by the book Sacred Plants of India by Nanditha Krishna and M. Amrithalingam.
The book, says Santhosh, highlights how plants have been revered in India since ancient times. He believes this sacred regard helped preserve many valuable species.