Cold hardiness & minimum temperature

Is Persicaria orientalis (Persicaria orientalis)cold hardy? Hardiness zone & min temp

Also called kiss-me-over-the-garden-gate, prince's feather.

More about persicaria orientalis

About Persicaria orientalis

Persicaria orientalis · also called kiss-me-over-the-garden-gate, prince's feather · flowering

Kiss-me-over-the-garden-gate is a tall, fast hardy annual reaching 1.5-2 m in a single season, with large heart-shaped leaves and arching, tassel-like sprays of rosy-pink flowers from midsummer to frost. An old cottage-garden favourite, it self-sows freely, draws bees and hummingbirds, and makes a quick informal screen at the back of a sunny border.

Cold limit: USDA 2-11 (grown as a frost-tender annual) (10 to 30°C)

Watch for — Slow, frost-sensitive start: Seedlings are tender and resent cold. Sow after the last frost or start indoors with warmth, as cold checks germination and early growth.

What persicaria orientalis's hardiness rating actually means

Yes — persicaria orientalis is genuinely cold hardy. Rated RHS H7 and USDA 2-11 (grown as a frost-tender annual), 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 2-11 (grown as a frost-tender annual) — 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. Persicaria orientalis is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for persicaria orientalis 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 persicaria orientalis go outside or overwinter — and where?

Plant it out within USDA 2-11 (grown as a frost-tender annual) 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 persicaria orientalis can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Persicaria orientalis hardiness — frequently asked questions

Is persicaria orientalis cold hardy?

Yes — persicaria orientalis is genuinely cold hardy. Rated RHS H7 and USDA 2-11 (grown as a frost-tender annual), it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Persicaria orientalis is hardy across USDA 2-11 (grown as a frost-tender annual); 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 persicaria orientalis can survive?

Minimum survivable temperature is roughly below about −20 °C. Persicaria orientalis is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is persicaria orientalis?

Persicaria orientalis is rated USDA 2-11 (grown as a frost-tender annual) and RHS H7 — Hardy in the severest European continental winters.

Can persicaria orientalis survive winter outside?

Plant it out within USDA 2-11 (grown as a frost-tender annual) 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 persicaria orientalis 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.