Cold hardiness & minimum temperature

Is Spotted Mandarin (Prosartes maculata)cold hardy? Hardiness zone & min temp

Also called Spotted mandarin, Nodding mandarin, Spotted fairybells, Spotted disporum.

More about spotted mandarin

About Spotted Mandarin

Prosartes maculata · also called Spotted mandarin, Nodding mandarin · flowering

Prosartes maculata is an uncommon native wildflower of the Appalachian Mountains and adjacent uplands, typically found in rich, shaded, deciduous forests from Pennsylvania south to Georgia. Its upright, leafy stems bear nodding creamy-white flowers distinctively spotted with purple in mid-spring, followed by pale straw-coloured, 3-lobed berries. It requires deep, moist woodland soil in full to partial shade and is best suited to naturalised plantings alongside other shade-tolerant natives. The berries are suspected to be toxic based on genus relationships; treat as mildly toxic to cats and dogs.

Cold limit: USDA 5-8 · RHS H6 (-25 to 28°C)

What spotted mandarin's hardiness rating actually means

Yes — spotted mandarin is genuinely cold hardy. Rated RHS H6 and USDA 5-8, 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 5-8 — 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 about −20 to −15 °C. Spotted Mandarin is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for spotted mandarin 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 spotted mandarin go outside or overwinter — and where?

Plant it out within USDA 5-8 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 spotted mandarin can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Spotted Mandarin hardiness — frequently asked questions

Is spotted mandarin cold hardy?

Yes — spotted mandarin is genuinely cold hardy. Rated RHS H6 and USDA 5-8, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Spotted Mandarin is hardy across USDA 5-8; 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 spotted mandarin can survive?

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

What hardiness zone is spotted mandarin?

Spotted Mandarin is rated USDA 5-8 and RHS H6 — Hardy throughout the UK and northern Europe.

Can spotted mandarin survive winter outside?

Plant it out within USDA 5-8 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 spotted mandarin 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.