Back From the Brink- World’ Smallest Water-Lily

                                          Photo Credit: RBG Kew

The importance of botanic gardens for conservation was reemphasized by the success of cracking the enigma of growing a rare species of African water-lily by the Royal Botanic Gardens, Kew. The feat was achieved by Kew's top propagation 'code-breaker', horticulturist Carlos Magdalena. Waterlilies are among the most ancient of flowering plants.

The rare species of African waterlily (Nymphaea thermarum), believed to be the smallest waterlily in the world with pads less than 1cm in diameter was discovered in 1985 by German botanist Professor Eberhard Fischer of Koblenz-Landau University. It was endemic to just one known location in Mashyuza, Rwanda. The plant grows in damp mud caused by the overflow of a hot spring. Water reaches the surface at 50C but the plant colonizes an area where the water has cooled to a temperature of 25C.

The species disappeared from Mashyuza about two years ago due to over-exploitation of the hot spring that fed the habitat. Right now no plant is known to survive in the wild.

Professor Eberhard Fischer had transported a few specimens to Bonn Botanic Gardens soon after its discovery. The species proved extremely difficult to propagate.

As part of a conservation plant exchange between Bonn and Kew, a handful of seeds and pre-germinated seedlings were transported to Kew in July 2009. Professor Carlos took the propagation as a challenge. The professor, who has a track record of bringing the rarest and most difficult plants back from the brink, unraveled the secrets of successfully propagating Nymphaea thermarum over many months of assiduous work.

The plant did not grow submerged in the deep waters of lakes, rivers or marshes like other water lily. It grows in the damp conditions at the edge of a thermal hot spring. This was the vital clue needed to crack the code. The professor placed seeds and seedlings into pots of loam within small containers filled with water, thus keeping the water at the same level as the surface of the compost, at a temperature of 25°C. The plants started to improve and after a few weeks, eight plants began to grow very well. In November 2009 heralding a new era of success Kew's collection of Nymphea thermarum flowered for the first time. Now Kew has over 30 healthy plants growing very well.

Professor Eberhard Fischer says if the natural flow of water in its historic location can be restored, plants grown at Kew can then be reintroduced into the wild.

On Saturday 22 May 2010 visitors to Kew Gardens will be able to see Nymphaea thermarum on display.

Tahrcountry salutes Dr Carlos Magdalena. Here is an admirable example where individuals, by doing practical things with plants, can make a real difference to biodiversity conservation.