Growli

Overwintering guide

How to overwinter cosmos sulphureus 'bright lights'

Verdict
Stays outside
When
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
Hardiness
Cosmos sulphureus 'Bright Lights' is hardy to roughly USDA zone 2 — winter lows around -46°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 cosmos sulphureus 'bright lights' in winter

Cutting cosmos sulphureus 'bright lights' 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 cosmos sulphureus 'bright lights' care

Overwintering cosmos sulphureus 'bright lights' — FAQ

Does cosmos sulphureus 'bright lights' need to come indoors for winter?

Cosmos sulphureus 'Bright Lights' is hardy to roughly USDA zone 2 — winter lows around -46°C. That means it can stay outside all winter in most temperate gardens. Cosmos sulphureus 'Bright Lights' 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 cosmos sulphureus 'bright lights' for winter?

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

How often should I water cosmos sulphureus 'bright lights' in winter?

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

What kills cosmos sulphureus 'bright lights' over winter?

Cutting cosmos sulphureus 'bright lights' 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.