Native water lilies hibernate outside in the garden pond, while exotic water lilies should hibernate indoors.
Water lilies (Nymphaea) are the adornment of every garden pond and can even be cultivated in a small trough and brought to bloom. In larger water bodies, water lilies can easily overwinter. Since the pond does not freeze completely, the rhizome is not endangered. With smaller garden ponds and exotic types of water lilies, you have to take care of the hibernation yourself if you want the water lilies to inspire with their bloom again next summer.
Native water lilies overwinter
Native species are quite robust and do not require special protection. Most domestic water lilies can remain in the garden pond all year round if certain requirements are met.
So that the pond plants are well protected from frost, the roots of the water lily must be about 60 centimeters below the water surface. Even if the pond freezes over, the plants are usually well protected at this depth. Only if you are cultivating exotic varieties or if the pond is shallow do you have to look for ways to overwinter the water lilies outside the body of water.
In order for native water lilies to survive the cold season as unscathed as possible, it depends on how you winterize the garden pond.
The following work is necessary:
- Let the water pump run empty
- Winter water pump frost-free
- Remove rotten and diseased parts from the water lily
- Prune out plants that are too close together
- Remove sludge
- Insert ice preventer
Our recommendation:
Sludge forms when parts of plants die and collect on the bottom of the pond. The sludge releases hydrogen sulfide gas. If the exhaust fumes are concentrated under the ice sheet, they can damage the water lilies.
» Tip: You do not have to dispose of digested sludge. It's a good fertilizer.
Wintering water lilies in the mini pond
On the balcony and terrace it is quite attractive to create a mini pond in old zinc tubs, troughs and planters. Water lilies can also be openedintegrate well in a small area and make them bloom.
But with the first frost, it also becomes dangerous in the mini pond for native and actually hardy water lilies. If the container freezes completely, the water and nutrient uptake is cut off and the plants cannot survive.
Small ponds can be moved completely into the house. This allows the plant to be left in the water. The mini pond is placed in a light and cool place. The temperatures should not exceed ten degrees. If the containers are too large and unwieldy, drain the water and transfer the plants to buckets or larger planters.
Winter Exotic Water Lilies
Exotic water lilies cannot be left in the pond. By November at the latest, but in any case before the first frost, the plants are taken out of the water and placed in buckets.
The vessels are placed in a cool but frost-free place in the basement, in the attic or in the garage. Complete darkness should not prevail. Water lilies need some daylight even in winter.
The vessel should be filled with water. Check the water level regularly, water lilies must never dry out.
➔ Wintering exotic water lilies in the greenhouse
If you have a greenhouse, tropical water lilies can be overwintered there bright and warm. With temperatures around 20 degrees, which can be reached in a heated pool, the plants do not take a winter break and continue to grow and flower in the cold season.
➔ Overwinter exotic water lilies in the fridge
As paradoxical as this may sound, you can also keep the water lilies through the winter in the fridge. The plant is taken out of the water. The rhizome is dried and cleaned. Then fill a bag with sand and put the tuber in.
» Important: The rhizome of the water lily must be completely surrounded by sand.
After the winter, when the pond water has already warmed up a bit, the tuber can be put back into the ground and put into the water in the plant basket.
When can the water lilies go back into the garden pond?
Exotic water lilies as well as domestic plants that are cultivated in a shallow mini-pond should not be returned outside until mid-May. It is best to wait until the ice saints have said goodbye in mid-May and no more frost is to be expected.