Cold hardiness & minimum temperature

Is Lopsided Begonia (Begonia obliqua)cold hardy? Hardiness zone & min temp

Also called Lopsided Begonia, Oblique Begonia.

More about lopsided begonia

About Lopsided Begonia

Begonia obliqua · also called Lopsided Begonia, Oblique Begonia · houseplant

Begonia obliqua is a fibrous-rooted tropical species native to South America and the Caribbean, recognised by its noticeably asymmetric (oblique) leaf bases — a feature that gives the plant its common name. It produces small pale pink to white flowers and grows best in warm, humid indoor environments with bright indirect light. The single most important care fact is to protect it from draughts and cold, as temperatures below 13 °C cause leaf drop and stem die-back. Begonia obliqua is toxic to cats and dogs.

Cold limit: USDA 10-12 (indoor in most climates) · RHS H1b (15–26 °C)

Watch for — Leaf drop from cold or draughts: Sudden leaf loss often follows a cold draught, an open window in winter, or temperatures dropping below 13 °C; move the plant to a stable, warm position away from radiators and draughts.

What lopsided begonia's hardiness rating actually means

Lopsided Begonia 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 H1b means: Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season. On the US scale that maps to USDA 10-12 (indoor in most climates) — 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 10 °C (sustained cold below this is damaging). Lopsided Begonia has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for lopsided begonia as it gets too cold:

Below about about 10 °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 lopsided begonia go outside or overwinter — and where?

It can holiday outdoors in summer once nights are reliably above 10 °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 lopsided begonia can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1b figure above.

Lopsided Begonia hardiness — frequently asked questions

Is lopsided begonia cold hardy?

Lopsided Begonia 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. Lopsided Begonia can only live outside year-round in genuinely frost-free climates (roughly USDA 10-12 (indoor in most climates)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature lopsided begonia can survive?

What hardiness zone is lopsided begonia?

Lopsided Begonia is rated USDA 10-12 (indoor in most climates) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can lopsided begonia survive winter outside?

It can holiday outdoors in summer once nights are reliably above 10 °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 lopsided begonia below its minimum temperature?

Below about about 10 °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.