Cold hardiness & minimum temperature

Is Greater Woodrush (Luzula sylvatica)cold hardy? Hardiness zone & min temp

Also called Greater woodrush, Wood rush, Great woodrush.

More about greater woodrush

About Greater Woodrush

Luzula sylvatica · also called Greater woodrush, Wood rush · flowering

Luzula sylvatica is a vigorous, clump-forming evergreen sedge-like plant native to woodland margins and shaded hillsides across Europe and western Asia. It thrives in deep shade and moist, humus-rich soil, making it one of the best ground-cover plants for difficult shady spots under trees. The most important care fact is that it tolerates heavy shade and dry shade once established better than almost any other grass-like plant. Not listed as toxic by the ASPCA; considered pet-safe.

Cold limit: USDA 5-9 · RHS H7 (-20°C to 25°C)

What greater woodrush's hardiness rating actually means

Yes — greater woodrush 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. Greater Woodrush is built for winter — once established it takes hard frost and snow in its stride.

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

Greater Woodrush hardiness — frequently asked questions

Is greater woodrush cold hardy?

Yes — greater woodrush 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. Greater Woodrush 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 greater woodrush can survive?

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

What hardiness zone is greater woodrush?

Greater Woodrush is rated USDA 5-9 and RHS H7 — Hardy in the severest European continental winters.

Can greater woodrush 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 greater woodrush 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.