There are only seven species of Hardy water lilies that are recognized in The Water lilies, and monograph from 1905 about the genus Nymphaea, by Henry S. Conrad. However, botanist today claim there are far more varieties, because many species will develop different characteristics based on the regions in which they grow. Eventually these characteristics create such an individual plant, that it deserves its own name.
Individuality of a Hardy
There are many species set down on the list that follows. There are many varieties that are included in the doubtful species, but to refuse to recognize these, would mean each varieties would need to be renamed, so it is simply easier to keep them in the species originally claimed for them.
All of the Hardies bloom in the daytime, usually for three days in a row. Usually the flowers will float on the surface, but if there is crowding, sometimes the flower will get thrust up over the surface. Hardies do best in the North Temperate Zone, and are not found on the Pacific slope of North America. Some foliage is even found growing in Alaska.
The changeable, a group of Hardy water lilies, is perhaps the most fascinating. The name says it all! The bud will bloom with one color, but by the end of the day the flower begins to change to another color. So over the span of the three days, it will be three different colors. Catalogues normally refer to these as sunset shades. Some lilies are called extensive growers; this refers to water lilies with blooms and leaves that cover 10-12 square feet of a poll or lake. A Medium Grower will cover 8-10 square feet, and a Small Growercovers four square feet or less.
