Cold hardiness & minimum temperature

Is Broomsedge Bluestem (Andropogon virginicus)cold hardy? Hardiness zone & min temp

Also called Broomsedge Bluestem, Broomsedge, Virginia Bluestem.

More about broomsedge bluestem

About Broomsedge Bluestem

Andropogon virginicus · also called Broomsedge Bluestem, Broomsedge · flowering

Broomsedge Bluestem is a native warm-season bunch grass of eastern North America, instantly recognised by its intense copper-orange to reddish-brown winter colour, which persists well into spring. It colonises old fields, roadsides, and disturbed land, making it a key species in meadow restoration. Though vigorous and sometimes weedy, it provides exceptional winter structure and wildlife habitat.

Cold limit: USDA 5-10 · RHS H6 (-23°C to 42°C)

Watch for — Fire risk in dry conditions: The persistent dry straw-like foliage is highly combustible in winter and early spring. Do not plant immediately adjacent to structures or wood fencing in dry climates. In regions that practice prescribed burning, it is a keystone fire-adapted species.

What broomsedge bluestem's hardiness rating actually means

Yes — broomsedge bluestem is genuinely cold hardy. Rated RHS H6 and USDA 5-10, 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 5-10 — 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. Broomsedge Bluestem is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for broomsedge bluestem 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 broomsedge bluestem go outside or overwinter — and where?

Plant it out within USDA 5-10 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 broomsedge bluestem can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H6 figure above.

Broomsedge Bluestem hardiness — frequently asked questions

Is broomsedge bluestem cold hardy?

Yes — broomsedge bluestem is genuinely cold hardy. Rated RHS H6 and USDA 5-10, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Broomsedge Bluestem is hardy across USDA 5-10; 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 broomsedge bluestem can survive?

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

What hardiness zone is broomsedge bluestem?

Broomsedge Bluestem is rated USDA 5-10 and RHS H6 — Hardy throughout the UK and northern Europe.

Can broomsedge bluestem survive winter outside?

Plant it out within USDA 5-10 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 broomsedge bluestem 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.