Overwintering guide
How to overwinter iron butterfly tiarella
Winter watering
No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.
The mistake that kills iron butterfly tiarella in winter
Cutting iron butterfly tiarella 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 iron butterfly tiarella care
Overwintering iron butterfly tiarella — FAQ
Does iron butterfly tiarella need to come indoors for winter?
Iron Butterfly Tiarella is hardy to roughly USDA zone 4 — winter lows around -34°C. That means it can stay outside all winter in most temperate gardens. Iron Butterfly Tiarella 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 iron butterfly tiarella for winter?
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
How often should I water iron butterfly tiarella in winter?
No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.
What kills iron butterfly tiarella over winter?
Cutting iron butterfly tiarella 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.