Growli

Overwintering guide

How to overwinter white horehound

Verdict
Stays outside
When
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
Hardiness
White Horehound is hardy to roughly USDA zone 3 — winter lows around -40°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 white horehound in winter

Cutting white horehound 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 white horehound care

Overwintering white horehound — FAQ

Does white horehound need to come indoors for winter?

White Horehound is hardy to roughly USDA zone 3 — winter lows around -40°C. That means it can stay outside all winter in most temperate gardens. White Horehound 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 white horehound for winter?

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

How often should I water white horehound in winter?

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

What kills white horehound over winter?

Cutting white horehound 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.