Water Lilies
Family Nymphaeaceae

by Robert Fenner
Reprinted with permission, from Bob's website in San Diego:  www.wetwebmedia.com
Aquarticles

Water lilies are the quintessential aquatic garden plants; for many people water features are "water-lily ponds". These ubiquitous livestock are well-deserving of their popularity; hardy, long-lived, with blossoms of almost every color, water lilies abound in their practical and esthetic value to the aquatic gardener.

Taxonomy, Relation to Other Groups:
Though there are about sixty-five species of water lilies in seven genera found worldwide, the genus Nymphaea ("nim-figh-ah") is the genus of modern water lilies, in the similar named family Nymphaeaceae. I like this choice of the Latin word for "nymphs" for water lilies. How appropriate that these plants are named for minor goddesses that inhabit fountains and rivers; a perfect tie-in with the aquatic environment.

Nymphaea are grouped by scientific classification in the larger category, order Araceae. You know other "arum" members; these were some of the first terrestrial flowering plants, invading the land back in the Devonian Period (some 180 million years ago). The stately magnolias are also arums; look at their and the water lily's large flowers. Both share ancient characteristic "redundancy" in their parts; multiple petal, sepals, and each is 'perfect', bearing both pistils and stamens.

Origins, Size, Distribution:
We owe the greatest debt to Monsieur Latour-Marliac of Southern France for the hybridization and introduction of  90% of existing hardy varieties from 1885-1890; but water lilies and lotus have been kept and pictured by ancient Chinese, Persians and Egyptians for thousands of years.

Size range of lilies may surprise you; they span from the tiny pygmaea from China with blooms the size of a quarter, up to Victoria lilies with pads so large (several feet across) that they can support a human.

Distribution of the original Nymphaea species is virtually world-wide in tropical and temperate freshwaters. Yellow lilies originated from N. mexicana (syn. N. flava) native to Florida and Mexico, pinks have as one of their parents the Cape Cod lily, N. odorata rosea. Red varieties originally came from the Swedish water lily, N. alba rubra.

There are water-lilies that hail from Egypt, Australia, southern Africa, India, the U.S.... they and their sport mutations and hybrids (variously named by their originators) have been introduced everywhere on the planet where there is "free" (non-frozen) water and humans.

Hardy and Tropical Varieties:
There are two "groups" of water lilies with definite differences in shape, structure and growing requirements; the hardy and tropicals.

For large enough systems it's nice to have a mix of hardy, tropical (night and day blooming) lilies.

Hardy / Tropical
1) Cold tolerant / Removed and stored in winter.

2) White and warm flower colors / Warm and cool color flowers; only; yellow to garnet red, purples, blues, even green.

3) Day blooming / Day and night-blooming types

4) Flower stems ending at water / Flower stems terminating several inches above water.

5) Smaller flowers and leaves / Flowers and leaves larger.

6) Typical plant size 5-10' square / Plants 24' square plus.

A Truly Giant Water-Lily
The night-blooming tropical water lilies include the amazing, gigantic Amazon water lily Victoria regia (V. amazonica) named in honor of Queen Victoria.

This south American giant has leaves up to seven feet across, with edges turned up about three inches in height. The pads' undersides are a nightmarish array of thorns up to an inch long. You may see this monster if you visit a public garden that can afford the pool size and heating cost to sustain it's tropical temperature.

Another Victoria, V. cruziana (Trickeri) is easier fare for slightly lower temperatures. It's leaves are a little smaller with correspondingly higher turned-up edges.

Water Lily Selection:
There are a dizzying assortment of varieties to choose from. Bear the following questions in mind when making a selection; "How big will these plants get?", "Are they day, night bloomers, odoriferous?" "Where can I place this plant so that it receives adequate light and space?" "What color, shape flowers do I want?"

My advice is to practice with hardy types of lilies first; they are less money and "hardier"; not surprisingly.

The "common" colloquial names for lily varieties come and go with popularity and supplanting by novel hybrids. The following is my personal list of 'standards' in the trade (& color blossoms) that are in my opinion best suited for all applications:

Hardy Water Lilies:
Albida (white)       
Attraction (white)
Chromatella (yellow)
Escarboucle (vermilion red)
Gladstone (white)

Tropical Water Lilies
Day Bloomers
August Koch (lavender blue)
Mrs. Pring (white)
Panama-Pacific (reddish purple)
Pennsylvania (bright blue)

Night Bloomers
Paul Hariot (apricot)
Dentata magnifica (white)
Wm. Falconer (garnet red)
Rubra rosea (carmine)
Helvola (pygmy yellow)
Missouri (creamy white)

Water lilies are purchased from water garden mail-order outfits, local nurseries, and sometimes "fish" stores and fellow hobbyists. Most grow like proverbial "weeds" (Plants we've yet to find a practical use for), so please do "share the wealth".

Pots/Planting:
Hardy water lilies have got to be one of the easiest plants to grow in the world. All that is needed is to press a good few inches of the sprouting root or rhizome into soil, leaving the growing tip above and cover with sand, gravel and possibly a stone to prevent the plant floating out. Hardy types are planted at a 45 degree angle against the side of their container, tropicals should be planted level in the center in as much sun as possible, in calm, quiet water.

Hardys are planted out in early Spring and flower in about six weeks. They may be placed out till late Summer, but you may have to wait till after Winter to see the fruit of your labors.

Periodic and Annual Care:
The basics of water-lily care are a minimum 3-4 hours of direct sun, decent water quality, removal of dead leaves (yellow-brown) and control of any insect pests. Aphids, cutworms can be easily and safely controlled by spraying them with a five percent solution of Ortho's Volck (tm) Oil Spray.

Fertilization and Separating/Re-Potting:
I'll mention these together, as they should both be done about once a year. There are references that "plug" the use of organic and loose nutrients (blood and bone meals, cow and other manures); I'm so against these practices, I won't elaborate on them. Instead, you are encouraged to utilize inorganic feeding "tablets" or possibly "granules" on an annual basis when you remove, clean and separate your plant-stocks.

This is a big job that should be approached in a planned, systematic manner, as it involves large scale disruption of the system and potential for injury.

It is a good practice to remove and replace all or a good part of the potting soil and cover every year. "Older" non-living portions of tubers are discarded and the growing tips of hardys and tropicals and the corms of the latter are re-planted with new fertilizer.

Take care not to over-plant your pond with too many lilies, they need room to spread out; leave room for water to show between the leaves. Don't cover the pond water's surface any more than 60-70 percent. "Normal size" hardy lilies need a two-gallon container each, tropicals a bushel basket, and Victorias a swimming pool.

Soil can be from an ordinary garden with no peat moss, rotted wood or pesticide contaminants. Use pea gravel graded to large enough stone material to discourage "rooting" of plants by your livestock.

Some folks boost flower production by periodic (monthly) fertilizer feedings, iron supplements and more; I generally find this unnecessary. It is dangerous to slip-slide on biological pond surfaces and sometimes too much of these chemicals getting loose can be dangerous to plants and fishes. If you are going to "push" your plants, construct a "fertilizing" stick to jam tablets into their surrounding soil while standing safely outside.

Over-wintering outside of the pond is necessary for all areas where the water freezes down to the lilies. By the first signs of frost, pull the containers (or plants) out of the pool and remove all the older long leaves and blossoms. Store the bare rooted plants with some wet soil in sealed plastic bags (or "pickle" buckets) out of the light and freezing cold for next Spring. Maybe you should include a label so you can tell which color/variety you're replanting the following year? Good idea.

When can you re-plant? After the last frost in your geographical area, ideally for tropicals when the water temperature is in the 60's and rising.

Reproduction:
Nymphaea propagate in three ways; by splitting asexually at the rhizome and at the center of mature leaves (some of the tropicals), and sexually by seed. Asexual buds may be separated when they are a few inches long each, and viviparous tropical "pups" can be cut away with a sharp knife, potted, and placed in shallow water when they develop roots.

Most lilies are sold and cultivated as rhizomes or tubers, but you can grow them from fertile seeds. They can be self-fertilizing or "manipulated" with a cover and "brushed" with the pollen of another plant (hardy for hardy, tropical/tropical). This is no simple feat; see Strawn below for insights/help.

Summary:
There are no flowering plants that are easier to grow in ponds than water lilies; nor any that rival them in attractiveness and color-range.

With your first efforts at their cultivation you will be successful and become a "nymphaea maniac" (note to Editors, not a nymphomaniac; please don't misspell)

Bibliography/Further Reading:

Masters, Charles O. 1974. Encyclopedia of the Water Lily. T.F.H. Publications, NJ.

Randall, Louis E. 1986. The astonishing Victoria water lilies at Longwood Gardens. The Green Scene 5/86.

Strawn, Kirk. 1988. Hybridization of hardy water lilies. Water Gardening Journal 3/88.

Uber, William C. 1988, Water Gardening Basics. Dragonflyer Press, CA.

Wischnath, Lothar. 1995. An introduction to water lily cultivation. Tropical Fish Hobbyist 7/95.