Overwintering guide
How to overwinter amethyst sea holly
Winter watering
No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.
The mistake that kills amethyst sea holly in winter
Cutting amethyst sea holly 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 amethyst sea holly care
Overwintering amethyst sea holly — FAQ
Does amethyst sea holly need to come indoors for winter?
Amethyst Sea Holly is hardy to roughly USDA zone 3 — winter lows around -40°C. That means it can stay outside all winter in most temperate gardens. Amethyst Sea Holly 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 amethyst sea holly for winter?
Tidy and mulch in late autumn; leave the plant undisturbed until spring.
How often should I water amethyst sea holly in winter?
No winter watering needed in open ground. Containers only need water in long dry, frost-free spells.
What kills amethyst sea holly over winter?
Cutting amethyst sea holly 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.