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