Author: Mgr. Milan Blažek.
Waterlilies are aquatic plants. Collection in Chotobuz Botanic garden shows their beauty and variability.
The Genus of Waterlilies
Waterlilies are aquatic plants. They have flashy rhizome at a bottom where roots, leaves and flowers grow from. Flowers are large floating on a water surface or standing out as of tropical species. They have 4 sepals and petals in higher number growing in a spiral. There are about 40, mostly tropical, species described. In temperate climate of Europe and Asia grow European White Waterlily (Nymphaea alba) and Common White Waterlily (Nymphaea candida). In North Europe, Asia and North America grows Pygmy Waterlily (N. tetragona). Other North American species are Fragrant White Waterlily (N. odorata) and its subspecies (N. odorata subsp. tuberosa)
Flower buds and rhizomes of some waterlilies have been used for cooking or as pickled vegetable. Waterlilies contain several bio-active substances as myricetin, sesquiterpenoid alkaloids and tanstuffs. Rhizomes have been used in traditional folk medicine for its calming and antibacterial effect when curing caught or bowel diseases. Mucoid substances also help with healing mucous membranes.
Hybridization of Waterlilies
The hybridization didn’t have such significant steps forward in time and progress as irises or daylilies, for instance. Waterlilies already have had a perfect flower shape and they have brought basic colors from original species. There were high quality hybrids of waterlilies even 100 years ago. At that time, a leading hybridizer was French botanist and gardener Latour Marliac, whose garden exists until today. European wild waterlilies have more compact rhizomes, which makes them suitable for smaller ponds and his hybrids have also advantage of not seeding itself, which is good for keeping true cultivars. Large and systematic breeding of waterlilies started in North America in second half of the last century. Its results are plants with mostly running rhizomes, which are in flower shape similar to Marliac’s waterlilies, but they come in more forms, colors and number of new cultivars. The biggest difference was in breeding of deep pink waterlilies and in hybrids getting together pink and yellow color.
Colors and Sizes of Waterlilies – Genetic Resources
Elementary species for hybridization of garden waterlilies were those of medium size, but all hardy waterlilies were bred in-between with an aim to get together different sizes of the plants and flower colors of other species. The smallest waterlilies came from Hardy Waterlily (Nymphaea pygmaea hort.) which was found in Finland. It is most likely a mutation of Pygmy Waterlily (N. tetragona).
Wild waterlilies, ancestors of cultivars, grow in temperate climate of North half of Europe, Asia and North America. Main flower color of these species is white, but some red pigments could be found in some plants of wild populations of European White Waterlily (N. alba) and Common White Waterlily (N. candida). Pink shades have its origin in North American Fragrant White Waterlily or Beaver Root (N. odorata) and American White Waterlily (N. tuberosa).
Pink red and red flower colors do not evolve from tropical species, where it is often, but from a red mutation of European White Waterlily from Sweden. This rare red flowered mutation was found in Närke (Nerike) lake area. Commonly grown ´Froebeli´ cultivar came from it as a waterlily of a smaller size. Its color joined together with waterlilies of a richer flower shape gave rise of many red flowered cultivars. The flower shape came from all waterlily species, but the richest ones resembling of a chrysanthemum have rhizomes typical for American species, which gives their origin away.
Yellow color is not to be found in any of Euro/Asian species of temperate climate, but of subtropical Central America. They are Mexican Waterlily (N. mexicana) also called Banana Waterlily and its close relative Yellow Waterlily (Nymphaea flava) from Florida. Their hybrids are quite hardy and they come in all sizes from miniature to the biggest ones. The Mexican Waterlily influence is not only recognized in the yellow color but also in a leave pattern. They are spotted on both or at least bottom side. Pygmy Waterlily (N. tetragona) is valuable source of breeding qualities, too. There are just a few of its subtle cultivars much preferred for small ponds. Plants of bigger size are indeed more vital and mostly they winter better over.
Very first collection of waterlilies in Pruhonice is dated back to the beginning of 20th century, but it ceased. There are still two cultivars alive in a Waterlily Bay in Park. Others could be found in different nurseries or survive as nameless plants. First systematic gathering of waterlily cultivars in Czech started a couple non-professional growers (K. Schäfer, L. Guth, J. Rehor, S. Sykora).
Waterlily Collection in Chotobuz
A new collection was started in the sixties. It is the only collection from our gene pools which is not in a chronological order. There are four ponds with different depth to suit plants the best and to show their qualities as typical. It is related to a plant size. In general wild plants and also cultivars range from miniatures, with mature leaves of 5cm, to foliage ten times bigger. When we consider leave size and other plant segments relation, than a water depth need to be from 20cm up to 1m. But it could be smaller or bigger according to plant size.
Since seventies of the last century a new afford in Pruhonice botanic garden started to complete the waterlily collection from all available sources. It was from domestic suppliers but also from Germany, Switzerland, USA and from the birthplace of modern waterlilies, the Marliac’s nursery in France. Within few years broad cooperation established with a great help of Mr.K.Wachter (GE) one of the best expert on waterlily cultivars and Mr.V.Hribal (CZ) with whom we had lots in common from the beginnings. Different sources had different names for the same plant and it was possible we had several plants with the same name in that time we must carefully compare. In total there were almost 300 items in the collection, including named but also nameless waterlilies.
To determine nameless plants, it needs extensive experience due to waterlily variability. Increased interest in it has brought positive changes in quality of grown assortment. There are more American cultivars, but also high quality old cultivars are still in commercial supply. That is different from irises and daylilies but similar to roses and peonies. They have more in common for garden use than botanically, which is apparent in their German names: Rosen (roses), Pfingstrosen (peonies), Seerosen (waterlilies).
Translation: Marketa Machackova