Cold hardiness & minimum temperature

Is Persian Catmint (Nepeta mussinii)cold hardy? Hardiness zone & min temp

Also called Persian Catmint, Mussini Catmint.

More about persian catmint

About Persian Catmint

Nepeta mussinii · also called Persian Catmint, Mussini Catmint · flowering

Persian Catmint is a compact, low-growing species native to the Caucasus and Iran, producing dense spikes of small violet-blue flowers above soft, silvery-green aromatic foliage. It is an excellent front-of-border or edging plant, highly attractive to bees and pollinators. Drought-tolerant and easy to grow in well-drained sunny positions.

Cold limit: USDA 4–8 · RHS H7 (−25°C to 35°C)

Watch for — Short-lived in warm, wet winters: Can be short-lived as a perennial in regions with warm, wet winters (USDA zones 8–9). Treat as a biennial in such conditions, or ensure very sharp drainage and good winter airflow.

What persian catmint's hardiness rating actually means

Yes — persian catmint 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. Persian Catmint is built for winter — once established it takes hard frost and snow in its stride.

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

Persian Catmint hardiness — frequently asked questions

Is persian catmint cold hardy?

Yes — persian catmint 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. Persian Catmint 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 persian catmint can survive?

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

What hardiness zone is persian catmint?

Persian Catmint is rated USDA 4–8 and RHS H7 — Hardy in the severest European continental winters.

Can persian catmint 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 persian catmint 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.