Cold hardiness & minimum temperature

Is Beardtongue 'Husker Red' (Penstemon digitalis)cold hardy? Hardiness zone & min temp

Also called Husker Red Beardtongue, White Beardtongue, Foxglove Beardtongue.

More about beardtongue 'husker red'

About Beardtongue 'Husker Red'

Penstemon digitalis · also called Husker Red Beardtongue, White Beardtongue · flowering

An award-winning native North American perennial bearing white to pale pink tubular flowers above striking burgundy-red foliage from late spring through midsummer. 'Husker Red' is exceptionally cold-hardy, drought-tolerant once established, and an excellent pollinator plant. A 1996 Perennial Plant of the Year. Mildly toxic if ingested; keep away from browsing livestock.

Cold limit: USDA 3-8 · RHS H7 (-35 to 35°C)

Watch for — Root and crown rot: The most frequent killer — caused by heavy, waterlogged soil especially in winter. Plant in raised beds or very well-drained spots; avoid mulching over the crown.

What beardtongue 'husker red''s hardiness rating actually means

Yes — beardtongue 'husker red' 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. Beardtongue 'Husker Red' is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for beardtongue 'husker red' 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 beardtongue 'husker red' 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 beardtongue 'husker red' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Beardtongue 'Husker Red' hardiness — frequently asked questions

Is beardtongue 'husker red' cold hardy?

Yes — beardtongue 'husker red' 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. Beardtongue 'Husker Red' 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 beardtongue 'husker red' can survive?

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

What hardiness zone is beardtongue 'husker red'?

Beardtongue 'Husker Red' is rated USDA 3-8 and RHS H7 — Hardy in the severest European continental winters.

Can beardtongue 'husker red' 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 beardtongue 'husker red' 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.