Cold hardiness & minimum temperature

Is Brazilian Rain Tree Bonsai (Chloroleucon tortum)cold hardy? Hardiness zone & min temp

Also called Brazilian rain tree, tornillo bonsai.

More about brazilian rain tree bonsai

About Brazilian Rain Tree Bonsai

Chloroleucon tortum · also called Brazilian rain tree, tornillo bonsai · houseplant

The Brazilian rain tree is a tropical bonsai treasure with fine bipinnate leaflets that fold shut at night and in rain, thorny zigzagging branches, and beautiful flaking bark. It loves warmth and humidity, making it one of the better tropicals for an indoor or greenhouse bonsai, though its spines and demand for steady heat ask for an attentive grower.

Cold limit: USDA 10-11 (kept warm indoors elsewhere) (18-30°C)

Watch for — Leaflet drop from cold or dryness: Temperatures below about 13°C or letting the rootball dry out triggers leaf shedding. Keep it warm and evenly moist year-round.

What brazilian rain tree bonsai's hardiness rating actually means

Brazilian Rain Tree Bonsai is not cold hardy. It is a tropical houseplant that dies if it is left out through frost — there is no zone where it overwinters outdoors in a UK or cold-US climate. Its RHS rating of H1c means: Warm-temperate — can summer outdoors but must come in well before the first frost. On the US scale that maps to USDA 10-11 (kept warm indoors elsewhere) — 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 5 °C (and never frost). Brazilian Rain Tree Bonsai has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for brazilian rain tree bonsai as it gets too cold:

Below about about 5 °C, growth stalls and the leaves start to show cold stress — dark, water-soaked, or yellowing patches.
A single light frost blackens the foliage; a hard freeze kills the whole plant, roots included, and it does not recover.
Even a cold, draughty windowsill or an unheated porch in winter can be enough to damage it permanently.

Can brazilian rain tree bonsai go outside or overwinter — and where?

It can holiday outdoors in summer once nights are reliably above 5 °C, in shade or dappled light, hardened off gradually.
Bring it back indoors well before the first autumn frost — do not wait for a frost warning, move it when nights drop toward 10-12 °C.
It will never overwinter outside in a temperate climate; the indoors is its winter home, full stop.

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 brazilian rain tree bonsai can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1c figure above.

Brazilian Rain Tree Bonsai hardiness — frequently asked questions

Is brazilian rain tree bonsai cold hardy?

Brazilian Rain Tree Bonsai is not cold hardy. It is a tropical houseplant that dies if it is left out through frost — there is no zone where it overwinters outdoors in a UK or cold-US climate. Indoor-only in almost every home. Brazilian Rain Tree Bonsai can only live outside year-round in genuinely frost-free climates (roughly USDA 10-11 (kept warm indoors elsewhere)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature brazilian rain tree bonsai can survive?

Minimum survivable temperature is roughly about 5 °C (and never frost). Brazilian Rain Tree Bonsai has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

What hardiness zone is brazilian rain tree bonsai?

Brazilian Rain Tree Bonsai is rated USDA 10-11 (kept warm indoors elsewhere) and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can brazilian rain tree bonsai survive winter outside?

It can holiday outdoors in summer once nights are reliably above 5 °C, in shade or dappled light, hardened off gradually. Bring it back indoors well before the first autumn frost — do not wait for a frost warning, move it when nights drop toward 10-12 °C. It will never overwinter outside in a temperate climate; the indoors is its winter home, full stop.

What happens to brazilian rain tree bonsai below its minimum temperature?

Below about about 5 °C, growth stalls and the leaves start to show cold stress — dark, water-soaked, or yellowing patches. A single light frost blackens the foliage; a hard freeze kills the whole plant, roots included, and it does not recover. Even a cold, draughty windowsill or an unheated porch in winter can be enough to damage it permanently.