A waterlily fit for a Queen

First new species of giant waterlily since 1840 is also world's largest

Woman standing on giant lily pad at Shaw's Garden (Missouri Botanical Garden), in front of the Linnean House, c1905. Public Domain.

When the “Longwood” hybrid of the giant waterlily Victoria amazonica was grown in the Princess of Wales Conservatory, at the Royal Botanic Gardens Kew, in 1995, its size was recognized as a world record by the Guinness Book with leaves reaching an astronishing 2.5 meters in diameter. But the record, like a pint of Guinness in Dublin, didn’t last long.

In 2022, a new and even larger species of giant waterlily from Bolivia was described, Victoria boliviana.   The first new species of the genus named since 1840, its circular floating leaves can grow up to 3.2 meters — or about ten and half feet — in diameter.

Is it the largest leaf in the world?  Yes, and no.  Among aquatic plants, absolutely.  Among plants with undivided leaves, seemingly so.  But among all leaves, at least with respect to the distance of the leaf’s longest axis, not even close.  The African palm tree Raphia regalis has leaves up to 82 feet in length, but they are divided into about 180 leaflets arranged along its Olympic-sized rachis.  Still, this is one seriously impressive leaf.

Tethered to the muck below by stalks up to twenty-six feet long, leaves have a network of ribs and cross-ribs on their undersurface that give the otherwise delicate leaf rigidity and capture pockets of air that keep it afloat.  With weight distributed evenly across its surface, a leaf can support up to 71 pounds!  This natural engineering marvel influenced nineteenth-century greenhouse designer Joseph Paxton, including his plans for the spectacular Crystal Palace erected in Hyde Park for the Great Exhibition of 1851.

Back to Victoria boliviana.  While new to science, this largest of all giant waterlilies was not entirely new to botanists and horiculturists.  Specimens had existed in herbaria for more than 170 years.  And Carlos Magdalena, a waterlily expert and senior horticulturist at Kew gardens had suspected a third species for years.  When seeds were sent to him in 2016 by two botanical gardens in Bolivia, he was able to grow them side by side with the two known species and confirm their uniqueness. Long before that, indigenous people of South America were not only aware of giant waterlilies, quite possibly including the newly named one, they used them as food, medicine, and the source of a black hair dye.

The same Paxton who was inspired to mimic the ribs of Victoria in greenhouse design was a key figure in a race to be first to entice of a giant waterlily to flower in London.  He achieved that distinction in a greenhouse he had built for the Duke of Devonshire at Chatsworth.  With a secret weapon — a heated water tank — he succeeded and had a Victoria amazonica bloom in 1849.

The new species, masquerading as a variant of Victoria amazonica, is just the latest in a long history of confusion regarding names in the genus.  In 1837, John Lindley named Victoria regia in honor of England’s new Queen who had ascended to the throne only months earlier.  His species description was in a publication for which only twenty-five copies were printed and presented to the Queen, select members of the aristocracy, and a few institutions.  Lindley got a lot of mileage out of the name and some historical accounts credit this patronym with saving Kew gardens which, if true, is something we can all be deeply grateful for.

Whether known to Lindley or not, the same species was independently named the very same year by German-born explorer Robert Schomburgk.  And whether known to the two of them or not, the species had already been named Euryale amazonica five years earlier.  The genus Euryale includes giant waterlilies found in Asia.  Most botanists agreed that the South American species deserved a separate genus and, given the popularity of Victoria, it was an easy sell.  There is evidence that the existence of the earlier name was noted by 1850 but the popularity of regia and its connection to the Queen kept it in popular, if incorrect, use. 

The latest molecular analyses indicate that Euryale and Victoria are sister genera, meaning that the relative relationships among giant waterlilies are the same whether classified as one or two genera.  This nomenclatural knot wasn’t unraveled until 1974 when Gillian Prance sorted it all out, retained Victoria, and acknowledged the priority of the earliest specific epithet amazonica.  Cultivation of V. amazonica in London unleashed a torrent of interest in giant waterlilies in the United Kingdom that soon crossed the pond to the United States.  People lined up to see these wondrous plants and special greenhouses were constructed for their display.

John Fisk Allen nurtured seeds given to him by Caleb Cope, president of the Pennsylvania Horticultural Society, and had the first blooming Victoria amazonica in North America in his garden in 1851.  He followed his horticultural feat with a beautifully illustrated book, Victoria regia; or the Great Water Lily of America, published in Boston in 1854, a book that some regard as the beginning of the era of chromolithography in the U.S.  A copy of the thin book, with half a dozen plates and fewer than twenty pages of text, was recently on the market for $60,000.

A second species, Victoria cruziana, from Argentina, was named soon after V. amazonica in 1840.  But it would not be until 2022 that a third species, and the largest yet, was formally recognized and named.  For me, word of every species discovery is a big deal.  But when that species has leaves approaching eleven feet in diameter, it’s a really big deal.

References

Prance, G. T. 1974. Victoria amazonica ou Victoria regia? Acta Amazonica 4: 5-8.

Prance, G. T. and J. R. Arias. 1975. A study of the floral biology of Victoria amazonica (Poepp.) Sowerby (Nymphaeaceae).  Acta Amazonica 5: 109-139.

Royal Collection Trust.  Victoria regia. 

Smith, L.T., et al. 2022.  Water lily genus Victoria (Nymphaeaceae) confirms a new species and has implications for its conservation.  Frontiers in Plant Science 13.