Growli

Overwintering guide

How to overwinter holly-leaved naiad

Verdict
Stays outside
When
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
Hardiness
Holly-leaved Naiad is hardy to roughly USDA zone 5 — winter lows around -29°C. That means it can stay outside all winter in most temperate gardens.

Winter watering

No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.

The mistake that kills holly-leaved naiad in winter

Cutting holly-leaved naiad 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 holly-leaved naiad care

Overwintering holly-leaved naiad — FAQ

Does holly-leaved naiad need to come indoors for winter?

Holly-leaved Naiad is hardy to roughly USDA zone 5 — winter lows around -29°C. That means it can stay outside all winter in most temperate gardens. Holly-leaved Naiad 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 holly-leaved naiad for winter?

Tidy and mulch in late autumn; leave the plant undisturbed until spring.

How often should I water holly-leaved naiad in winter?

No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.

What kills holly-leaved naiad over winter?

Cutting holly-leaved naiad 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.