Cold hardiness & minimum temperature

Is Field Chickweed (Cerastium arvense)cold hardy? Hardiness zone & min temp

Also called Field Chickweed, Field Mouse-Ear, Star Chickweed.

More about field chickweed

About Field Chickweed

Cerastium arvense · also called Field Chickweed, Field Mouse-Ear · flowering

A low, mat-forming perennial native to dry grasslands across the Northern Hemisphere. Field chickweed thrives in lean, sharply drained soil and full sun, producing a flush of white star-shaped flowers in spring. Virtually maintenance-free once established, it tolerates drought, poor soils, and hard frost, making it ideal for rock gardens and sunny borders.

Cold limit: USDA 2–7 · RHS H7 (-40°C to 25°C)

What field chickweed's hardiness rating actually means

Yes — field chickweed is genuinely cold hardy. Rated RHS H7 and USDA 2–7, 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 2–7 — 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. Field Chickweed is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for field chickweed 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 field chickweed go outside or overwinter — and where?

Plant it out within USDA 2–7 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 field chickweed can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Field Chickweed hardiness — frequently asked questions

Is field chickweed cold hardy?

Yes — field chickweed is genuinely cold hardy. Rated RHS H7 and USDA 2–7, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Field Chickweed is hardy across USDA 2–7; 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 field chickweed can survive?

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

What hardiness zone is field chickweed?

Field Chickweed is rated USDA 2–7 and RHS H7 — Hardy in the severest European continental winters.

Can field chickweed survive winter outside?

Plant it out within USDA 2–7 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 field chickweed 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.