I have seen different ways to divide hardy's is this the best info? is one time of year better than another? what about palnting depths? some lilies are cqapable of growing deeper right?
Thanks ...
Hardy Water Lilies Hardy water lilies are planted in much the same way as the tropicals using a loam garden soil and 2-3 fertilizer tablets. Hardy lilies grow horizontally across the container so a wide pot is necessary for planting (a 14 or 16inch fabric pot is the best container). The rhizome should be planted at one edge of the container with the rhizome planted at an angle of about 45 degrees with the crown exposed. Top with an inch or two of pea gravel or sand. The plant can be lowered to a depth of 6 inches to begin with, and then lowered to a depth of 12 - 18 inches as the plant grows. Hardy lilies should be planted in early spring and should be fertilized every 4-6 weeks. They bloom from June through September depending on the weather, and become dormant during the colder months. As spring approaches, growth will begin again.
Dividing and Repotting Hardy Water Lilies Hardy water lilies should be divided every two or three years depending on the plant container size. For the average to large size water lily, a five to seven gallon container is ideal. The best container will be shallow and wide. Small water lilies can be potted in a three to five gallon container.
Begin by removing the soil from the water lily using a water hose to expose the rhizomes. Select the best looking piece with good growth showing and cut to about three inches long, discard the remainder of the plant.
Trim away excess roots and any damaged foliage from the selected piece.If the water lily is to remain unpotted for any length of time, keep it in the shade with damp paper towels or newspaper covering the plant.
Prepare the container by filling about three fourths full of aquatic planting soil (clay loam is ideal) and add ten grams of a good fertilizer such as 10-20-10 for every gallon of soil.
Mound some soil against one side of the container and place the rhizome at a 45 degree angle with the cut edge against the pot and the growing point at the level the top of the soil will be. Add more soil to within a couple of inches of the top of the container. Firm the soil in place and add about one inch of pea gravel to cover the soil keeping it from covering the growing point of the plant. Gently add some water to the container and then slowly lower the plant into the pond.
If you place the plant just a few inches under the water for the first few weeks, you will get faster growth. After this, place the plant at the proper growing depth (Depth varis by cultivar). Fertilize the water lily every month with the same amount of fertilizer during the growing season.
source=
http://www.thewatergarden.com