Water lilies are tropical, flowering plants that live in freshwater. Water lilies actually root in the soil in bodies of water and the leaves and flowers float on top of the surface. These plants are often invasive because they can easily take over a still body of water. Lilies are very closely related to the Lotus and are usually used as an ornamental flower.
Choose the container to plant your water lilies. The best containers will measure approximately 15 inches around and 10 inches deep. If you use a smaller container you will end up with a smaller plant. Water lilies will grow according the container that you plant them in.
Fill the container a little more than halfway with a good all-purpose potting soil. Place the rhizome on top of the soil. The rhizome is the horizontal stem that has tubers growing from it that resembles a potato with stems growing from the eyes. Place the rhizome at an angle so that the plant will grow towards the center of the container.
Cover the rhizome with another inch of soil, or just enough soil to leave the very top of the rhizome showing out of the soil. The stems of the plant will be uncovered, but only 3/4 of the rhizome will be covered.
Place 1/4 to 1/2 inch of pea gravel on top of the soil. This is to prevent soil loss when the plant is placed into the pond. This will also help prevent your pond water from becoming cloudy from the dispersion of the soil in the water.
Water the water lilies until the soil is completely moist. Soil should be saturated with water to settle the plant into the soil and to wash out any small particles of soil before lowering it into the pond.
Lower the plant down into the pond slowly. The slower you lower the plant, the less likely you are to stir up any vegetation, which will keep the water clear. Place the plants at a depth low enough so that the water lily leaves rest just on top of the water. There should be at least 6-8 inches of water above the top of the container.
For best results there should be approximately 12 inches of water above the container. You can adjust this by removing supports in the water or raising the water level.
Push a 20-5-10 tablet fertilizer down into the soil of the water lily plant once a month. Follow the directions on the container to make sure the fertilizer is safe for pond fish, if you have them.
Remove the lilies from the pond in late fall and cut off all dying vegetation. Store the plants in a plastic bag with moist paper towels in a dark warm place until early spring when you can replant the lilies.