Cold hardiness & minimum temperature

Is Autumn Moor Grass (Sesleria autumnalis)cold hardy? Hardiness zone & min temp

Also called Autumn Moor Grass, Autumn Sesleria.

More about autumn moor grass

About Autumn Moor Grass

Sesleria autumnalis · also called Autumn Moor Grass, Autumn Sesleria · flowering

Autumn Moor Grass is a compact, semi-evergreen grass forming bright yellow-green mounds that light up shaded borders from midsummer onward. Its white flower spikes appear in late summer and autumn — unusually for a grass — giving it its common name. Exceptionally tolerant of dry shade, alkaline soils, and urban conditions, making it one of the most versatile, low-maintenance ornamental grasses. Non-toxic to pets.

Cold limit: USDA 5-9 · RHS H7 (-25 to 35°C)

Watch for — Leaf browning in cold winters: Semi-evergreen foliage may brown at the tips in severe winters. This is cosmetic; trim off the worst foliage in early spring before new growth begins.

What autumn moor grass's hardiness rating actually means

Yes — autumn moor grass is genuinely cold hardy. Rated RHS H7 and USDA 5-9, 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 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 below about −20 °C. Autumn Moor Grass is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for autumn 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 autumn moor grass 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 autumn 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.

Autumn Moor Grass hardiness — frequently asked questions

Is autumn moor grass cold hardy?

Yes — autumn moor grass is genuinely cold hardy. Rated RHS H7 and USDA 5-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Autumn Moor Grass 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 autumn moor grass can survive?

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

What hardiness zone is autumn moor grass?

Autumn Moor Grass is rated USDA 5-9 and RHS H7 — Hardy in the severest European continental winters.

Can autumn moor grass 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 autumn 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.