Cold hardiness & minimum temperature

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

Also called Walker's Low catmint.

More about nepeta 'walker's low'

About Nepeta 'Walker's Low'

Nepeta × faassenii 'Walker's Low' · also called Walker's Low catmint · flowering

A billowing, aromatic catmint smothered in lavender-blue flowers from late spring into autumn above soft grey-green foliage. Despite its name it is fairly tall and arching, forming a haze that bees and butterflies adore. Exceptionally tough, drought-tolerant, and deer-resistant, 'Walker's Low' rebounds vigorously after a hard shear and shines as a rose companion and border edger.

Cold limit: USDA 3-8 · RHS H7 (-34 to 30°C)

Watch for — Crown rot in wet soil: Waterlogged, heavy ground rots the crown; ensure sharp drainage and avoid winter wet.

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

Yes — nepeta 'walker's low' is genuinely cold hardy. Rated RHS H7 and USDA 3-8, 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 3-8 — 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. Nepeta 'Walker's Low' is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for nepeta '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 nepeta 'walker's low' go outside or overwinter — and where?

Plant it out within USDA 3-8 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 nepeta '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.

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

Is nepeta 'walker's low' cold hardy?

Yes — nepeta 'walker's low' is genuinely cold hardy. Rated RHS H7 and USDA 3-8, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Nepeta 'Walker's Low' is hardy across USDA 3-8; 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 nepeta 'walker's low' can survive?

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

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

Nepeta 'Walker's Low' is rated USDA 3-8 and RHS H7 — Hardy in the severest European continental winters.

Can nepeta 'walker's low' survive winter outside?

Plant it out within USDA 3-8 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 nepeta '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.