Growli

Overwintering guide

How to overwinter carnival squash

Verdict
Stays outside
When
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
Hardiness
Carnival Squash 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 carnival squash in winter

Cutting carnival squash 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 carnival squash care

Overwintering carnival squash — FAQ

Does carnival squash need to come indoors for winter?

Carnival Squash is hardy to roughly USDA zone 3 — winter lows around -40°C. That means it can stay outside all winter in most temperate gardens. Carnival Squash 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 carnival squash for winter?

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

How often should I water carnival squash in winter?

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

What kills carnival squash over winter?

Cutting carnival squash 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.