Cold hardiness & minimum temperature

Is Catmint 'Walker's Low' (Nepeta x faassenii)cold hardy? Hardiness zone & min temp

Also called Catmint, Garden Catmint, Faassen's Catmint.

More about catmint 'walker's low'

About Catmint 'Walker's Low'

Nepeta x faassenii · also called Catmint, Garden Catmint · flowering

A vigorous, drought-tolerant herbaceous perennial prized for its aromatic grey-green foliage and abundant lavender-blue flower spikes from late spring through summer. 'Walker's Low' is a compact, mounding cultivar that attracts pollinators and cats alike. Deadheading encourages a second flush of bloom. Not listed as toxic to pets by ASPCA.

Cold limit: USDA 4-8 · RHS H7 (-20 to 35°C)

Watch for — Crown rot: Caused by waterlogged or poorly drained soil, especially over winter. Plant on a slight slope or in raised beds with gritty soil to ensure drainage.

What catmint 'walker's low''s hardiness rating actually means

Yes — catmint 'walker's low' 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. Catmint 'Walker's Low' is built for winter — once established it takes hard frost and snow in its stride.

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

Catmint 'Walker's Low' hardiness — frequently asked questions

Is catmint 'walker's low' cold hardy?

Yes — catmint 'walker's low' 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. Catmint 'Walker's Low' 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 catmint 'walker's low' can survive?

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

What hardiness zone is catmint 'walker's low'?

Catmint 'Walker's Low' is rated USDA 4-8 and RHS H7 — Hardy in the severest European continental winters.

Can catmint 'walker's low' 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 catmint 'walker's low' 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.