Cold hardiness & minimum temperature

Is Mr Bowling Ball Arborvitae (Thuja occidentalis 'Bobozam')cold hardy? Hardiness zone & min temp

Also called Mr. Bowling Ball Arborvitae, Globe Arborvitae.

More about mr bowling ball arborvitae

About Mr Bowling Ball Arborvitae

Thuja occidentalis 'Bobozam' · also called Mr. Bowling Ball Arborvitae, Globe Arborvitae · flowering

A dwarf, naturally ball-shaped evergreen with fine, feathery, sage-green to blue-green threadlike foliage that gives a soft texture unlike typical arborvitae. It keeps a neat sphere without shearing and stays small, suiting borders, foundations, and containers. It thrives in full sun to part shade with moist, well-drained soil and is exceptionally low-maintenance and cold-hardy.

Cold limit: USDA 3-8 (dwarf globe form) · RHS H7 (-37 to 30°C)

Watch for — Winter bronzing: Cold can bronze the soft foliage over winter; colour generally recovers in spring.

What mr bowling ball arborvitae's hardiness rating actually means

Yes — mr bowling ball arborvitae is genuinely cold hardy. Rated RHS H7 and USDA 3-8 (dwarf globe form), 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 (dwarf globe form) — 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. Mr Bowling Ball Arborvitae is built for winter — once established it takes hard frost and snow in its stride.

Concretely, for mr bowling ball arborvitae 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 mr bowling ball arborvitae go outside or overwinter — and where?

Plant it out within USDA 3-8 (dwarf globe form) 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 mr bowling ball arborvitae can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H7 figure above.

Mr Bowling Ball Arborvitae hardiness — frequently asked questions

Is mr bowling ball arborvitae cold hardy?

Yes — mr bowling ball arborvitae is genuinely cold hardy. Rated RHS H7 and USDA 3-8 (dwarf globe form), it lives outdoors all year and needs winter cold rather than protection from it. An outdoor plant. Mr Bowling Ball Arborvitae is hardy across USDA 3-8 (dwarf globe form); 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 mr bowling ball arborvitae can survive?

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

What hardiness zone is mr bowling ball arborvitae?

Mr Bowling Ball Arborvitae is rated USDA 3-8 (dwarf globe form) and RHS H7 — Hardy in the severest European continental winters.

Can mr bowling ball arborvitae survive winter outside?

Plant it out within USDA 3-8 (dwarf globe form) 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 mr bowling ball arborvitae 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.