Cold hardiness & minimum temperature

Is Koehne's rowan (Sorbus koehneana)cold hardy? Hardiness zone & min temp

Also called Koehne's rowan, Koehne rowan.

More about koehne's rowan

About Koehne's rowan

Sorbus koehneana · also called Koehne's rowan, Koehne rowan · flowering

Koehne's rowan is a slender, small deciduous tree from central China, valued for its delicate, elegantly pinnate foliage and graceful drooping clusters of pure white berries that age to ivory. Rare in cultivation and compact in size, it suits smaller gardens and provides good autumn leaf colour alongside long-lasting ornamental berry display.

Cold limit: USDA 5-7 · RHS H6 (-20 to 27°C)

What koehne's rowan's hardiness rating actually means

Yes — koehne's rowan is genuinely cold hardy. Rated RHS H6 and USDA 5-7, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H6 means: Hardy throughout the UK and northern Europe. On the US scale that maps to USDA 5-7 — 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 −20 to −15 °C. Koehne's rowan is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for koehne's rowan as it gets too cold:

It tolerates winter lows to about −20 to −15 °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 koehne's rowan go outside or overwinter — and where?

Plant it out within USDA 5-7 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 koehne's rowan can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Koehne's rowan hardiness — frequently asked questions

Is koehne's rowan cold hardy?

Yes — koehne's rowan is genuinely cold hardy. Rated RHS H6 and USDA 5-7, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Koehne's rowan is hardy across USDA 5-7; 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 koehne's rowan can survive?

Minimum survivable temperature is roughly about −20 to −15 °C. Koehne's rowan is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is koehne's rowan?

Koehne's rowan is rated USDA 5-7 and RHS H6 — Hardy throughout the UK and northern Europe.

Can koehne's rowan survive winter outside?

Plant it out within USDA 5-7 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 koehne's rowan below its minimum temperature?

It tolerates winter lows to about −20 to −15 °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.