Cold hardiness & minimum temperature

Is Paeonia lactiflora 'Karl Rosenfield' (Paeonia lactiflora 'Karl Rosenfield')cold hardy? Hardiness zone & min temp

Also called Karl Rosenfield peony.

More about paeonia lactiflora 'karl rosenfield'

About Paeonia lactiflora 'Karl Rosenfield'

Paeonia lactiflora 'Karl Rosenfield' · also called Karl Rosenfield peony · flowering

'Karl Rosenfield' is a vigorous heirloom herbaceous peony from 1908, famed for its large, fully double, ruffled deep crimson-red blooms on strong stems in late spring. Fully hardy and exceptionally long-lived, it makes an outstanding cut flower with light fragrance. It demands full sun, deep fertile well-drained soil and shallow planting to flower freely for generations.

Cold limit: USDA 3-8 · RHS H7 (-30 to 30°C)

What paeonia lactiflora 'karl rosenfield''s hardiness rating actually means

Yes — paeonia lactiflora 'karl rosenfield' is genuinely cold hardy. Rated RHS H7 and USDA 3-8, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H7 means: Hardy in the severest European continental winters. On the US scale that maps to USDA 3-8 — 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 below about −20 °C. Paeonia lactiflora 'Karl Rosenfield' is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for paeonia lactiflora 'karl rosenfield' as it gets too cold:

It tolerates winter lows to about −20 °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 paeonia lactiflora 'karl rosenfield' go outside or overwinter — and where?

Plant it out within USDA 3-8 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 paeonia lactiflora 'karl rosenfield' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Paeonia lactiflora 'Karl Rosenfield' hardiness — frequently asked questions

Is paeonia lactiflora 'karl rosenfield' cold hardy?

Yes — paeonia lactiflora 'karl rosenfield' is genuinely cold hardy. Rated RHS H7 and USDA 3-8, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Paeonia lactiflora 'Karl Rosenfield' is hardy across USDA 3-8; 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 paeonia lactiflora 'karl rosenfield' can survive?

Minimum survivable temperature is roughly below about −20 °C. Paeonia lactiflora 'Karl Rosenfield' is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is paeonia lactiflora 'karl rosenfield'?

Paeonia lactiflora 'Karl Rosenfield' is rated USDA 3-8 and RHS H7 — Hardy in the severest European continental winters.

Can paeonia lactiflora 'karl rosenfield' survive winter outside?

Plant it out within USDA 3-8 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 paeonia lactiflora 'karl rosenfield' below its minimum temperature?

It tolerates winter lows to about −20 °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.