Cold hardiness & minimum temperature

Is Skyracer Moor Grass (Molinia caerulea subsp. arundinacea 'Skyracer')cold hardy? Hardiness zone & min temp

Also called Skyracer moor grass, tall purple moor grass, Skyracer grass.

More about skyracer moor grass

About Skyracer Moor Grass

Molinia caerulea subsp. arundinacea 'Skyracer' · also called Skyracer moor grass, tall purple moor grass · flowering

Molinia caerulea subsp. arundinacea 'Skyracer' is one of the tallest ornamental grasses available, sending up towering flower stems above a relatively modest basal clump. Its purple-tinged spikelets in late summer sway dramatically in the breeze, and autumn brings vivid gold. Ideal for statement borders with moist, acidic soil.

Cold limit: USDA 4-9 · RHS H7 (-25°C to 32°C)

What skyracer moor grass's hardiness rating actually means

Yes — skyracer moor grass is genuinely cold hardy. Rated RHS H7 and USDA 4-9, 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 4-9 — 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 below about −20 °C. Skyracer Moor Grass is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for skyracer moor grass 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 skyracer moor grass go outside or overwinter — and where?

Plant it out within USDA 4-9 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 skyracer moor grass can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Skyracer Moor Grass hardiness — frequently asked questions

Is skyracer moor grass cold hardy?

Yes — skyracer moor grass is genuinely cold hardy. Rated RHS H7 and USDA 4-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Skyracer Moor Grass is hardy across USDA 4-9; 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 skyracer moor grass can survive?

Minimum survivable temperature is roughly below about −20 °C. Skyracer Moor Grass is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is skyracer moor grass?

Skyracer Moor Grass is rated USDA 4-9 and RHS H7 — Hardy in the severest European continental winters.

Can skyracer moor grass survive winter outside?

Plant it out within USDA 4-9 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 skyracer moor grass 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.