Growli

Overwintering guide

How to overwinter water speedwell

Verdict
Stays outside
When
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
Hardiness
Water Speedwell is hardy to roughly USDA zone 4 — winter lows around -34°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 water speedwell in winter

Cutting water speedwell 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 water speedwell care

Overwintering water speedwell — FAQ

Does water speedwell need to come indoors for winter?

Water Speedwell is hardy to roughly USDA zone 4 — winter lows around -34°C. That means it can stay outside all winter in most temperate gardens. Water Speedwell 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 water speedwell for winter?

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

How often should I water water speedwell in winter?

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

What kills water speedwell over winter?

Cutting water speedwell 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.