Cold hardiness & minimum temperature

Is Sun Flare Rose (Rosa 'Sun Flare')cold hardy? Hardiness zone & min temp

Also called Sun Flare, JACjem, Sunflare.

More about sun flare rose

About Sun Flare Rose

Rosa 'Sun Flare' · also called Sun Flare, JACjem · flowering

Sun Flare is an award-winning yellow floribunda with clusters of clear, lightly licorice-scented double blooms above glossy, disease-resistant foliage. The compact, rounded plant flowers freely from early summer to frost, holding its bright yellow well. Tidy and bushy, it suits borders and pots. Roses are pet-safe, so it is a worry-free choice in pet-friendly gardens.

Cold limit: USDA 5-9 (garden-hardy) · RHS H6 (15-26°C)

What sun flare rose's hardiness rating actually means

Yes — sun flare rose is genuinely cold hardy. Rated RHS H6 and USDA 5-9 (garden-hardy), 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 5-9 (garden-hardy) — 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. Sun Flare Rose is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for sun flare rose 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 sun flare rose go outside or overwinter — and where?

Plant it out within USDA 5-9 (garden-hardy) 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 sun flare rose can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Sun Flare Rose hardiness — frequently asked questions

Is sun flare rose cold hardy?

Yes — sun flare rose is genuinely cold hardy. Rated RHS H6 and USDA 5-9 (garden-hardy), it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Sun Flare Rose is hardy across USDA 5-9 (garden-hardy); 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 sun flare rose can survive?

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

What hardiness zone is sun flare rose?

Sun Flare Rose is rated USDA 5-9 (garden-hardy) and RHS H6 — Hardy throughout the UK and northern Europe.

Can sun flare rose survive winter outside?

Plant it out within USDA 5-9 (garden-hardy) 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 sun flare rose 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.