Cold hardiness & minimum temperature

Is Jostaberry (Ribes × nidigrolaria)cold hardy? Hardiness zone & min temp

Also called jostaberry, josta berry.

More about jostaberry

About Jostaberry

Ribes × nidigrolaria · also called jostaberry, josta berry · edible

The jostaberry is a thornless, vigorous hybrid of blackcurrant and gooseberry, combining the disease resistance of one with the larger fruit of the other. Hardy and easy-going, it bears glossy near-black berries with a flavour between the two parents, ripening in midsummer. Productive even in cooler, partly shaded gardens, it needs no second pollinator.

Cold limit: USDA 3-8 · RHS H6 (-30 to 28°C)

Watch for — Overgrown, congested bushes: Its vigour quickly produces a dense thicket that shades out fruiting wood; remove the oldest stems each winter to keep an open, productive framework.

What jostaberry's hardiness rating actually means

Yes — jostaberry is genuinely cold hardy. Rated RHS H6 and USDA 3-8, 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 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 about −20 to −15 °C. Jostaberry is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for jostaberry 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 jostaberry 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 jostaberry can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Jostaberry hardiness — frequently asked questions

Is jostaberry cold hardy?

Yes — jostaberry is genuinely cold hardy. Rated RHS H6 and USDA 3-8, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Jostaberry 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 jostaberry can survive?

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

What hardiness zone is jostaberry?

Jostaberry is rated USDA 3-8 and RHS H6 — Hardy throughout the UK and northern Europe.

Can jostaberry 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 jostaberry 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.