Do I cut my water-lilies down for winter and if so, when?

I have a water garden/pond and this is the first year I have had lilies and I am not sure how to get them ready for winter. Any help will be grateful.

Do I cut my water-lilies down for winter and if so, when?
Lillies do not have to be cut back but it is always a good idea to remove the dead leaves from your pond. Any dead material in your pond should be removed in the fall and spring. How deep are they? Lillies should be overwintered in the deepest part of the pond – where the water does not freeze. Even though they die out they should not be allowed to freeze solid. The frost line varies depending on your location – in NW Indiana it is around 20 inches. My pond lilies are deeper than 20” plus I put a trough heater (bought at TSC) in the pond over winter to keep a hole open. Pond lilies are fertilizer pigs but do not fertilize in the fall because it will stimulate growth you do not want. Fertilize in the spring. Other than that these plants are hardy and if they are in pots they will require you to divide them in a year or two but that is another subject.
Reply:I don't have many, but I'm bring them inside till April.
Reply:gff