Cold hardiness & minimum temperature

Is Lobbi Japanese Cedar (Cryptomeria japonica 'Lobbii')cold hardy? Hardiness zone & min temp

Also called Lobbi Japanese Cedar, Lobbii Japanese Cedar, Cryptomeria 'Lobbii'.

More about lobbi japanese cedar

About Lobbi Japanese Cedar

Cryptomeria japonica 'Lobbii' · also called Lobbi Japanese Cedar, Lobbii Japanese Cedar · flowering

Cryptomeria japonica 'Lobbii' is a stately, fast-growing cultivar of Japanese Cedar with densely arranged, bright green foliage and a strongly conical to columnar habit. It is more compact than the species type, with tightly clustered branchlets. Suitable for large gardens and parks in temperate oceanic climates with high rainfall.

Cold limit: USDA 6-9 · RHS H5 (-15 to 25°C)

Watch for — Winter bronzing: Foliage turns bronze-brown in cold, dry winters, particularly when exposed to wind. This is a normal physiological response in colder climates, not disease — colour returns to green in spring. Protect young trees with windbreak fleece in exposed positions.

What lobbi japanese cedar's hardiness rating actually means

Yes — lobbi japanese cedar is genuinely cold hardy. Rated RHS H5 and USDA 6-9, it lives outdoors all year and needs winter cold rather than protection from it. Its RHS rating of H5 means: Hardy in most of the UK and in cold winters. On the US scale that maps to USDA 6-9 — 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 about −15 to −10 °C. Lobbi Japanese Cedar is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for lobbi japanese cedar as it gets too cold:

It tolerates winter lows to about −15 to −10 °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 lobbi japanese cedar go outside or overwinter — and where?

Plant it out within USDA 6-9 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 lobbi japanese cedar can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H5 figure above.

Lobbi Japanese Cedar hardiness — frequently asked questions

Is lobbi japanese cedar cold hardy?

Yes — lobbi japanese cedar is genuinely cold hardy. Rated RHS H5 and USDA 6-9, it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Lobbi Japanese Cedar is hardy across USDA 6-9; 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 lobbi japanese cedar can survive?

Minimum survivable temperature is roughly about −15 to −10 °C. Lobbi Japanese Cedar is built for winter — once established it takes hard frost and snow in its stride.

What hardiness zone is lobbi japanese cedar?

Lobbi Japanese Cedar is rated USDA 6-9 and RHS H5 — Hardy in most of the UK and in cold winters.

Can lobbi japanese cedar survive winter outside?

Plant it out within USDA 6-9 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 lobbi japanese cedar below its minimum temperature?

It tolerates winter lows to about −15 to −10 °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.