Cold hardiness & minimum temperature

Is all gold Japanese forest grass (Hakonechloa macra 'All Gold')cold hardy? Hardiness zone & min temp

Also called all gold Japanese forest grass, All Gold hakone grass.

More about all gold japanese forest grass

About all gold Japanese forest grass

Hakonechloa macra 'All Gold' · also called all gold Japanese forest grass, All Gold hakone grass · houseplant

Hakonechloa macra 'All Gold' is a luminous, clump-forming Japanese forest grass with uniformly golden-yellow blades that cascade in graceful arching mounds. Unlike 'Aureola' it has no green striping — the entire blade is pure gold. It glows in shaded borders and containers, brightening dark corners. Deciduous and slow-growing, it needs consistently moist, rich soil in part shade.

Cold limit: USDA 5-9 · RHS H6 (-15 to 24°C)

What all gold japanese forest grass's hardiness rating actually means

Yes — all gold japanese forest grass is genuinely cold hardy. Rated RHS H6 and USDA 5-9, 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 5-9 — 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 −20 to −15 °C. all gold Japanese forest grass is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for all gold japanese forest grass 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 all gold japanese forest 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 all gold japanese forest grass can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

all gold Japanese forest grass hardiness — frequently asked questions

Is all gold japanese forest grass cold hardy?

Yes — all gold japanese forest grass is genuinely cold hardy. Rated RHS H6 and USDA 5-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. all gold Japanese forest 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 all gold japanese forest grass can survive?

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

What hardiness zone is all gold japanese forest grass?

all gold Japanese forest grass is rated USDA 5-9 and RHS H6 — Hardy throughout the UK and northern Europe.

Can all gold japanese forest 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 all gold japanese forest grass 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.