Growli

Overwintering guide

How to overwinter 'red baron' onion

Verdict
Stays outside
When
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
Hardiness
'Red Baron' Onion 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 'red baron' onion in winter

Cutting 'red baron' onion 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 'red baron' onion care

Overwintering 'red baron' onion — FAQ

Does 'red baron' onion need to come indoors for winter?

'Red Baron' Onion is hardy to roughly USDA zone 3 — winter lows around -40°C. That means it can stay outside all winter in most temperate gardens. 'Red Baron' Onion 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 'red baron' onion for winter?

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

How often should I water 'red baron' onion in winter?

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

What kills 'red baron' onion over winter?

Cutting 'red baron' onion 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.