Overwintering guide
How to overwinter american mountain ash
Winter watering
No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.
The mistake that kills american mountain ash in winter
Cutting american mountain ash 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 american mountain ash care
Overwintering american mountain ash — FAQ
Does american mountain ash need to come indoors for winter?
American mountain ash is hardy to roughly USDA zone 2 — winter lows around -46°C. That means it can stay outside all winter in most temperate gardens. American mountain ash 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 american mountain ash for winter?
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
How often should I water american mountain ash in winter?
No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.
What kills american mountain ash over winter?
Cutting american mountain ash 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.