Cold hardiness & minimum temperature

Is Hardy Cyclamen (Cyclamen hederifolium)cold hardy? Hardiness zone & min temp

Also called Ivy-leaved Cyclamen, Sowbread.

More about hardy cyclamen

About Hardy Cyclamen

Cyclamen hederifolium · also called Ivy-leaved Cyclamen, Sowbread · flowering

Hardy cyclamen is an autumn-flowering tuberous perennial prized for pink-to-white blooms that appear before its marbled, ivy-shaped leaves. It thrives in dappled shade under deciduous trees, naturalising in dry, humus-rich soil. Summer-dormant, it needs a dry rest. One of the toughest cyclamen, surviving hard winter frosts once established.

Cold limit: USDA 5-9 (fully hardy garden plant) · RHS H5 (5-15°C)

What hardy cyclamen's hardiness rating actually means

Yes — hardy cyclamen is genuinely cold hardy. Rated RHS H5 and USDA 5-9 (fully hardy garden plant), it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H5 means: Hardy in most of the UK and in cold winters. On the US scale that maps to USDA 5-9 (fully hardy garden plant) — the zones where it can be left outdoors year-round.

New to these scales? The USDA hardiness zone map explained covers how the zone numbers work, and you can find your own zone with the zone finder.

Minimum temperature — and what happens below it

Minimum survivable temperature is roughly about −15 to −10 °C. Hardy Cyclamen is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for hardy cyclamen as it gets too cold:

It tolerates winter lows to about −15 to −10 °C once established.
Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root.
First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.

Can hardy cyclamen go outside or overwinter — and where?

Plant it out within USDA 5-9 (fully hardy garden plant) and it overwinters with little or no help.
It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy.
The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

Work back from your local frost dates with the frost-date calculator: the last spring frost and first autumn frost are what really decide when hardy cyclamen can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H5 figure above.

Hardy Cyclamen hardiness — frequently asked questions

Is hardy cyclamen cold hardy?

Yes — hardy cyclamen is genuinely cold hardy. Rated RHS H5 and USDA 5-9 (fully hardy garden plant), it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Hardy Cyclamen is hardy across USDA 5-9 (fully hardy garden plant); it belongs in the ground or a frost-proof container, not on a windowsill, and many types actively need a cold winter to perform.

What is the minimum temperature hardy cyclamen can survive?

Minimum survivable temperature is roughly about −15 to −10 °C. Hardy Cyclamen is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is hardy cyclamen?

Hardy Cyclamen is rated USDA 5-9 (fully hardy garden plant) and RHS H5 — Hardy in most of the UK and in cold winters.

Can hardy cyclamen survive winter outside?

Plant it out within USDA 5-9 (fully hardy garden plant) and it overwinters with little or no help. It does not want to come indoors — a warm winter room actually weakens a hardy plant by denying it dormancy. The real risks in its range are waterlogging, wind-rock on young plants, and a late hard frost on new growth — not ordinary winter cold.

What happens to hardy cyclamen below its minimum temperature?

It tolerates winter lows to about −15 to −10 °C once established. Below its rated zone, the visible damage is browned or blackened top growth and, in the worst case, a killed crown or root. First-year, newly planted, or container-grown specimens are noticeably less hardy than established garden plants — the roots are exposed.