Growli

Overwintering guide

How to overwinter aster 'october skies'

Verdict
Stays outside
When
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
Hardiness
Aster 'October Skies' 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 aster 'october skies' in winter

Cutting aster 'october skies' 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 aster 'october skies' care

Overwintering aster 'october skies' — FAQ

Does aster 'october skies' need to come indoors for winter?

Aster 'October Skies' is hardy to roughly USDA zone 3 — winter lows around -40°C. That means it can stay outside all winter in most temperate gardens. Aster 'October Skies' 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 aster 'october skies' for winter?

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

How often should I water aster 'october skies' in winter?

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

What kills aster 'october skies' over winter?

Cutting aster 'october skies' 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.