Cold hardiness & minimum temperature

Is Scarlet Leucothoe (Leucothoe fontanesiana 'Scarletta')cold hardy? Hardiness zone & min temp

Also called Scarlet Leucothoe, Scarletta Fetterbush, Drooping Leucothoe, Dog Hobble.

More about scarlet leucothoe

About Scarlet Leucothoe

Leucothoe fontanesiana 'Scarletta' · also called Scarlet Leucothoe, Scarletta Fetterbush · flowering

Leucothoe fontanesiana 'Scarletta' (sold under the trade name Zeblid) is a compact, arching, evergreen shrub from the mountain woodlands of the eastern United States, prized for its vivid scarlet-red new growth in spring that matures to glossy dark green before turning rich burgundy in winter, providing year-round colour. It prefers reliably moist, acidic soil in partial to full shade, making it an excellent ground cover under trees and on shaded slopes. The critical care requirement is consistent soil moisture — it wilts rapidly in dry conditions. All parts are toxic to cats, dogs, and horses.

Cold limit: USDA 5-8 · RHS H6 (-23 to 30 °C)

What scarlet leucothoe's hardiness rating actually means

Yes — scarlet leucothoe 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. Scarlet Leucothoe is built for winter — once established it takes hard frost and snow in its stride.

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

Scarlet Leucothoe hardiness — frequently asked questions

Is scarlet leucothoe cold hardy?

Yes — scarlet leucothoe 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. Scarlet Leucothoe 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 scarlet leucothoe can survive?

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

What hardiness zone is scarlet leucothoe?

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

Can scarlet leucothoe 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 scarlet leucothoe 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.