This section is from the book "The Gardener V2", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
The petals, being numerous, and inserted on the side of the seed-vessel in a freer manner, give the flowers a more graceful appearance than those of Nuphar have. Few objects are more graceful and interesting than well - cultivated Nymphaeas, and our own British Water-Lily is scarcely inferior to those of the tropics. It should be cultivated in every piece of water in the country, where ornament is an object.
This is our native species, and it enjoys rather a wide geographical range over Europe, and central and northern Asia. The leaves are deeply heart-shaped, the lobes overlapping. Flowers in June, July, and August.
The leaves are roundish oval, heart-shaped; the lobes open, deep, and spreading. Flowers in July and August. Native of Siberia. Not often seen in gardens in this country, but worthy of extensive favour.
A North American species, of which I have no experience in the north, but which succeeds well along with other hardy Water-Lilies in southern counties. The leaves are round, deeply heart-shaped, with open spreading lobes. Flowers in July and August.