Overwintering guide
How to overwinter giant water lily
Winter watering
Cut watering right back — giant water lily uses far less while growth slows, and cold, wet compost is the usual cause of winter root rot. Stop feeding until spring.
The mistake that kills giant water lily in winter
Watering on the same schedule as summer. In winter that keeps the roots sodden while the plant is barely drinking, and giant water lily rots from the base.
More giant water lily care
Overwintering giant water lily — FAQ
Does giant water lily need to come indoors for winter?
Giant Water Lily is hardy to roughly USDA zone 10 — winter lows around -1°C. That means it will not survive frost and needs to come inside. Giant Water Lily is frost-tender, so overwintering means bringing it inside and letting it rest rather than pushing it to grow. Move it indoors well before the first frost, give it the brightest spot you have (light levels indoors drop sharply in winter), and keep it away from both cold window glass and hot radiators — the swing between the two does more damage than the cold itself.
When should I move giant water lily for winter?
Bring indoors when nights start dropping below about 10°C, ahead of the first frost.
How often should I water giant water lily in winter?
Cut watering right back — giant water lily uses far less while growth slows, and cold, wet compost is the usual cause of winter root rot. Stop feeding until spring.
What kills giant water lily over winter?
Watering on the same schedule as summer. In winter that keeps the roots sodden while the plant is barely drinking, and giant water lily rots from the base.