Cold hardiness & minimum temperature

Is Tian Shan Everlasting (Helichrysum thianschanicum)cold hardy? Hardiness zone & min temp

Also called Tian Shan Everlasting, Silver Spike, Liquorice Plant.

More about tian shan everlasting

About Tian Shan Everlasting

Helichrysum thianschanicum · also called Tian Shan Everlasting, Silver Spike · flowering

Helichrysum thianschanicum is a woolly, mound-forming semi-evergreen subshrub native to the dry, gravelly steppe and mountain slopes of the Tian Shan range on the Kazakhstan–Xinjiang border. It is grown primarily for its striking silver-white foliage and produces small yellow flowerheads on upright stems in summer. The single most critical care requirement is excellent drainage — it evolved in extremely lean, dry soils and will rot quickly in moisture-retentive ground. Helichrysum is not formally listed by the ASPCA; treat as mildly-toxic as a precaution.

Cold limit: USDA 5–9 · RHS H5 (-15 °C to 30 °C)

Watch for — Stem rot in wet conditions: Wet winters or poorly drained containers cause the crown and stems to collapse. Plant on a raised bed or mound with extra grit, and site where rain drains away rapidly.

What tian shan everlasting's hardiness rating actually means

Yes — tian shan everlasting is genuinely cold hardy. Rated RHS H5 and USDA 5–9, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H5 means: Hardy in most of the UK and in cold winters. On the US scale that maps to USDA 5–9 — 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 −15 to −10 °C. Tian Shan Everlasting is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for tian shan everlasting as it gets too cold:

It tolerates winter lows to about −15 to −10 °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 tian shan everlasting go outside or overwinter — and where?

Plant it out within USDA 5–9 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 tian shan everlasting can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H5 figure above.

Tian Shan Everlasting hardiness — frequently asked questions

Is tian shan everlasting cold hardy?

Yes — tian shan everlasting is genuinely cold hardy. Rated RHS H5 and USDA 5–9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Tian Shan Everlasting is hardy across USDA 5–9; 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 tian shan everlasting can survive?

Minimum survivable temperature is roughly about −15 to −10 °C. Tian Shan Everlasting is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is tian shan everlasting?

Tian Shan Everlasting is rated USDA 5–9 and RHS H5 — Hardy in most of the UK and in cold winters.

Can tian shan everlasting survive winter outside?

Plant it out within USDA 5–9 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 tian shan everlasting below its minimum temperature?

It tolerates winter lows to about −15 to −10 °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.