Cold hardiness & minimum temperature

Is Matted Globularia (Globularia cordifolia)cold hardy? Hardiness zone & min temp

Also called Matted globularia, Heart-leaved globe daisy, Globe daisy.

More about matted globularia

About Matted Globularia

Globularia cordifolia · also called Matted globularia, Heart-leaved globe daisy · flowering

Globularia cordifolia is a dwarf, mat-forming evergreen perennial native to the limestone mountains of central and southern Europe, where it creeps across sunny, rocky outcrops. In summer it produces fluffy, powder-puff flowerheads of pale lavender-blue held just above a low mat of small, spoon-shaped, dark-green leaves. The paramount care requirement is very well-drained, neutral to alkaline soil in full sun — it is particularly intolerant of winter wet and waterlogged roots. Globularia is not listed in the ASPCA toxic plant database; classified as mildly-toxic out of caution as data is limited.

Cold limit: USDA 4-8 · RHS H7 (-30 to 25°C)

Watch for — Crown rot from winter wet: The most frequent cause of plant loss; heavy rainfall or clay soils that hold moisture around the crown through winter cause fatal rotting. Grow in raised beds, troughs, or on a slope, and consider covering with an open cloche in wet winters.

What matted globularia's hardiness rating actually means

Yes — matted globularia is genuinely cold hardy. Rated RHS H7 and USDA 4-8, 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 4-8 — 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. Matted Globularia is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for matted globularia 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 matted globularia go outside or overwinter — and where?

Plant it out within USDA 4-8 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 matted globularia can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Matted Globularia hardiness — frequently asked questions

Is matted globularia cold hardy?

Yes — matted globularia is genuinely cold hardy. Rated RHS H7 and USDA 4-8, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Matted Globularia is hardy across USDA 4-8; 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 matted globularia can survive?

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

What hardiness zone is matted globularia?

Matted Globularia is rated USDA 4-8 and RHS H7 — Hardy in the severest European continental winters.

Can matted globularia survive winter outside?

Plant it out within USDA 4-8 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 matted globularia 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.