Overwintering guide
How to overwinter scirpus lacustris
Winter watering
No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.
The mistake that kills scirpus lacustris in winter
Cutting scirpus lacustris hard back in autumn "to tidy up". That removes the growth that shelters the crown, and on some plants removes next season's flower buds entirely.
More scirpus lacustris care
Overwintering scirpus lacustris — FAQ
Does scirpus lacustris need to come indoors for winter?
Scirpus lacustris is hardy to roughly USDA zone 4 — winter lows around -34°C. That means it can stay outside all winter in most temperate gardens. Scirpus lacustris is properly hardy and overwinters outside without fuss. Tidy away anything dead or diseased, apply a mulch over the crown to steady soil temperatures, and otherwise leave it alone — many hardy plants actually need a cold period to flower and grow well the following year. Save hard pruning for the right season rather than doing it in autumn.
When should I move scirpus lacustris for winter?
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
How often should I water scirpus lacustris in winter?
No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.
What kills scirpus lacustris over winter?
Cutting scirpus lacustris hard back in autumn "to tidy up". That removes the growth that shelters the crown, and on some plants removes next season's flower buds entirely.