Maintenance and Care
Hardy water lilies grow horizontally, so a wide container is needed. A 14 or 16 inches fabric pot will be your best choice. The rhizome needs to be planted at one edge of the pot, angled at about 45 degrees, with the crown exposed. This should be topped with an inch or two of peas gravel or sand. Lower the plant to about 6 inches deep to begin, and lower to 12-16 inches as it begins to grow. Hardy's need to be planted in the early spring, and every 4-6 weeks will need to be fertilized. The Hardy's will bloom from June through September, depending on when the cooler weather moves in. They will be dormant through the cold months.
Re-potting and Dividing
Hardy Water Lilies will need to be divided every two to three years based on the size of container you have. The average to large lilies will need a 5-7 gallon container. Make sure it is shallow and wide. You can plant smaller lilies in 3-5 gallon containers.
When dividing, remove the soil from the lily by using a water hose to expose the rhizomes. Take the best looking piece, that has good growth showing, and cut to about 3 inches long. Trim away any excess roots or damaged foliage. If you are leaving the plant un-planted for any amount of time, be sure to keep in the shade with damp paper towels or newspaper coverings.
You should fill your container with about three fourths full of aquatic planting soil ( clay loam is best), and add ten grams of good fertilizer like 10-20-10 for every gallon of soil.
Pack soil into one side of the container so you can place the rhizome at a 45 degree angle, with the cut edge against the pot, and the growing point at the same level as where the top of the soil will be. Add soil to within a few inches of the top of the container. Make sure to soil is firmly packed, and then add one inch of pea gravel over the soil. Make sure the gravel does not cover the growing point. Gently add water and slowly lower the plant into the pond.
The way to promote the fasted growth is to place your plant just a few inches under the water for a few weeks. You can then move your plant to the proper depth of 12-18 inches of water over the plant. You will want to fertilize the lily every month with the same amount of fertilizer during the growing season!
