HARDY WATER LILIES
BY GEORGE EDGAR
Some of you may read the title and think “I don’t have a pond so this does not apply to me”. A water garden does not take a big pond. This past summer I had three water lilies in whiskey barrels on my driveway in full sun. The lilies bloomed off and on all summer. Before I had a pond I overwintered a lily in a 5 gallon bucket in my basement. This summer have your water garden in a container and then treat it as an annual or overwinter it in your basement, or some place that does not freeze.
To flower and flourish, a water lily needs care like any other perennial. Proper sunlight, the right kind of soil, the right kind of fertilizer at the right time, proper water depth, and pruning will determine the success of the plant.
Water lilies begin putting up their first floating leaves in April. The first ones may be smaller or darker in color than later ones. As the season unfolds, the leaves get larger. Each leaf lives three to four weeks then turns yellow and dies. Prompt removal of yellowing leaves at the soil level encourages new leaves to appear and keeps your pond clean. In May, the first flowers reach the surface. Each bloom lasts for about four days, opening and closing daily. As a flower is spent, it will slowly sink into the pond and should be pinched out like the dead leaves, to promote more flowering and to keep your pond clean. Debris in the bottom of the pond from spent leaves and flowers encourages string algae. Hardy water lilies flower from May until September with the peak season in June through August.
When planting water lilies use gummy clay soil from the garden that is free of clumps and organic matter that may float, or soil specifically for water plants, or a ceramic material made from clay that has been heated to a very hot temperature (Structure). It is usually used by gardeners to break up clay soil. Avoid any herbicide (weed killer) contaminated soil. Commercial potting soil should not be used because it contains vermiculite, perlite, and/or peat moss, which can float out of the pot and cloud the water.
Hardy water lilies like a larger pot, rather than one that is too small. One source recommended using a pot that is as large as your pond or water holding container on your driveway or yard can accommodate. Larger soil volume means bigger flowers and leaves. New lilies usually are sold in small containers and should be transplanted into a larger container. I use a round container that is about 16 inches in diameter and about 6 ˝ inches deep. This size will fit into a whiskey barrel plastic liner and also is about the right size for my pond. With this size of container, I usually have to divide my lilies and hardy water lotus every other year. This is best done in the spring when the plant shows growth and has a few new leaves. One reason I like “Structure” is because it does not get my hands all muddy when dividing the plants.
Hardy water lilies are grown from tubers that are typically 4 to 8 inches long and can have several growing points. Fill the pot one-quarter full with soil. Holding the tuber in one hand, place the tuber along one edge of the container at a 45-degree angle with the root pointing downward toward the opposite side of the container. Fill the soil in around the tuber until the soil is about 2 inches away from the top of the pot with the crown sticking out of the soil approximately one-half to 1 inch. It is very important to cover the top of each pot with at least a 1 inch layer of pea gravel or decorative gravel to avoid the soil floating away and to prevent cloudy water from exposed soil, unless you use a product like “Structure”. It does not float.
Regular fertilization will keep your hardy water lily blooming and growing well. Fertilizer tablets for water plants are the easiest to use. Push the tablets clear to the bottom of the pot at planting time in the spring and then at least once a month from April until the middle of August. I use three tablets in the spring in my 16 inch containers and then add two tablets each month. If you have a very large plant you may want to fertilize more often. Do not fertilize after August 15th so the plant can begin to go dormant for the winter.
Position the water lily so that it receives at least five or more hours of direct sunlight. The afternoon sun is best. Some varieties will flower at a reduced rate in less sunlight. More sun means more flowers. Also, locate the water lily so that the floating leaves are out of the turbulence of the waterfall or fountain spray. Water splashing on the top of the leaves will discolor or destroy them.
With the onset of fall, several things must be done to prepare the pond for winter. After a hard freeze or when plants die back, cut the spent foliage and place the plants in the deepest part of the water garden where they will over winter until next spring. A pond that is in the ground must be a minimum of 18 to 24 inches deep for plants to over winter. My fiberglass pond is 24 inches deep and freezes over every winter. However, the bottom of the pond that contains the plants does not freeze and so they survive.
If the pond is too shallow for over wintering your plants, you can install a pond heater. A good option is to use a small floating stock tank heater. This is mandatory if fish are kept in the pond all winter. The hole in the ice lets gas escape and allows air to come in. If you don’t use a pond heater, these plants should be pulled and stored in a cool area that is between 35 and 50 degrees F. Do not let them dry out. One year I over wintered my hardy water lilies by taking them out of the pot, removing all the soil, and storing the roots in a 5 gallon bucket of water in the basement.
“Introduction to Water Gardening” by
“The American Horticultural Society
Complete Guide to Water Gardening” by Peter Robinson. Published by DK
“Ortho’s All About Water Gardening” by
Greg and Sue Speichert. Published by Meredith Corporation, Ortho Books,