Growli

Overwintering guide

How to overwinter sea spleenwort

Verdict
Outside, protected
When
Mulch and move pots into shelter in late autumn, before the first hard frosts.
Hardiness
Sea Spleenwort is hardy to roughly USDA zone 8 — winter lows around -12°C. That means it survives outside in mild areas, but wants shelter in a hard winter.

Winter watering

Water rarely, and only in dry spells — winter wet is a bigger risk than winter cold. Make sure containers drain freely.

The mistake that kills sea spleenwort in winter

Leaving sea spleenwort in a pot standing in a saucer of water. Waterlogged compost freezes solid around the roots and kills plants that would have survived the cold perfectly well.

More sea spleenwort care

Overwintering sea spleenwort — FAQ

Does sea spleenwort need to come indoors for winter?

Sea Spleenwort is hardy to roughly USDA zone 8 — winter lows around -12°C. That means it survives outside in mild areas, but wants shelter in a hard winter. Sea Spleenwort can stay outside over winter in most areas, but appreciates some protection in a cold snap. Mulch generously over the root zone, move containers against a sheltered wall (pots freeze far harder than open ground), and have horticultural fleece ready for the worst nights. The roots are what you are protecting — top growth can be sacrificed and regrown.

When should I move sea spleenwort for winter?

Mulch and move pots into shelter in late autumn, before the first hard frosts.

How often should I water sea spleenwort in winter?

Water rarely, and only in dry spells — winter wet is a bigger risk than winter cold. Make sure containers drain freely.

What kills sea spleenwort over winter?

Leaving sea spleenwort in a pot standing in a saucer of water. Waterlogged compost freezes solid around the roots and kills plants that would have survived the cold perfectly well.