Cold hardiness & minimum temperature

Is Begonia 'Joe Hayden' (Begonia × 'Joe Hayden')cold hardy? Hardiness zone & min temp

Also called joe hayden begonia, rhizomatous dark begonia.

More about begonia 'joe hayden'

About Begonia 'Joe Hayden'

Begonia × 'Joe Hayden' · also called joe hayden begonia, rhizomatous dark begonia · houseplant

Begonia 'Joe Hayden' is a rhizomatous hybrid famed for very dark, near-black star-shaped leaves with red undersides and a glossy, almost metallic sheen. It spreads from a creeping rhizome and throws up sprays of pale pink flowers in late winter to spring. Give it bright indirect light, moderate humidity, warmth, and careful watering to keep the dark foliage rich.

Cold limit: USDA 10-11 (grown indoors in most US homes) · RHS H1b (18-26°C)

Watch for — Crispy leaf margins: Low humidity or dry heat browns the leaf edges. Raise ambient humidity and keep the plant clear of radiators and cold drafts.

What begonia 'joe hayden''s hardiness rating actually means

Begonia 'Joe Hayden' 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 10-11 (grown indoors in most US homes) — 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). Begonia 'Joe Hayden' has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for begonia 'joe hayden' 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 begonia 'joe hayden' 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 begonia 'joe hayden' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1b figure above.

Begonia 'Joe Hayden' hardiness — frequently asked questions

Is begonia 'joe hayden' cold hardy?

Begonia 'Joe Hayden' 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. Begonia 'Joe Hayden' can only live outside year-round in genuinely frost-free climates (roughly USDA 10-11 (grown indoors in most US homes)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature begonia 'joe hayden' can survive?

What hardiness zone is begonia 'joe hayden'?

Begonia 'Joe Hayden' is rated USDA 10-11 (grown indoors in most US homes) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can begonia 'joe hayden' 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 begonia 'joe hayden' 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.