Cold hardiness & minimum temperature

Is Begonia × tuberhybrida 'Pin-Up Flame' (Begonia × tuberhybrida 'Pin-Up Flame')cold hardy? Hardiness zone & min temp

Also called Pin-Up Flame Begonia, Picotee Tuberous Begonia.

More about begonia × tuberhybrida 'pin-up flame'

About Begonia × tuberhybrida 'Pin-Up Flame'

Begonia × tuberhybrida 'Pin-Up Flame' · also called Pin-Up Flame Begonia, Picotee Tuberous Begonia · flowering

Pin-Up Flame is a single-flowered tuberous begonia with large picotee blooms — creamy-yellow petals edged in glowing orange-red — held above bronze-green foliage. It flowers freely from summer to frost in cool, bright, shaded spots and dislikes heat and harsh sun. Compact and container-friendly, its tubers can be lifted and overwintered dry and frost-free for years of repeat display.

Cold limit: USDA 9-11 (lift and store tubers in colder zones) · RHS H2 (13-24°C)

What begonia × tuberhybrida 'pin-up flame''s hardiness rating actually means

Begonia × tuberhybrida 'Pin-Up Flame' is half-hardy (RHS H2). It survives a mild winter outdoors in a sheltered spot, but a hard frost kills it — so in colder zones it is lifted, potted, or grown as a tender plant. Its RHS rating of H2 means: Tender — survives a frost-free greenhouse or a very mild, sheltered spot. On the US scale that maps to USDA 9-11 (lift and store tubers in colder zones) — 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 1 to 5 °C — tolerates cold but no real frost. Begonia × tuberhybrida 'Pin-Up Flame' shrugs off cold nights but a real, sustained freeze will kill it.

Concretely, for begonia × tuberhybrida 'pin-up flame' as it gets too cold:

Down to roughly about 1 to 5 °C it copes, especially if dry and sheltered.
A sustained hard frost collapses the top growth; whether it returns depends on whether the roots, crown or tubers froze.
Wet cold is far more lethal than dry cold for this plant — soggy, frozen soil is the usual killer.

Can begonia × tuberhybrida 'pin-up flame' go outside or overwinter — and where?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 (lift and store tubers in colder zones) or a frost-free UK microclimate.
In colder zones, grow it in a pot you can move under cover, or lift its tubers/roots and store them frost-free over winter.
A south-facing wall, free-draining soil and a dry winter position can push it a full zone hardier than the books suggest.

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 × tuberhybrida 'pin-up flame' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H2 figure above.

Frost protection for borderline begonia × tuberhybrida 'pin-up flame'

Begonia × tuberhybrida 'Pin-Up Flame' is right on a hardiness edge in many gardens, so if you are pushing it, these measures buy it the margin it needs:

Mulch the crown or root zone deeply with bark, straw or leaf-mould before the first hard frost.
Move container plants against a warm wall or into an unheated but frost-free porch or greenhouse.
Fleece the top growth on the coldest nights, and keep it on the dry side — dry roots survive cold far better than wet ones.
Lift dahlia-type tubers or tender crowns after the first light frost blackens the foliage and store them somewhere cool but frost-free.

Begonia × tuberhybrida 'Pin-Up Flame' hardiness — frequently asked questions

Is begonia × tuberhybrida 'pin-up flame' cold hardy?

Begonia × tuberhybrida 'Pin-Up Flame' is half-hardy (RHS H2). It survives a mild winter outdoors in a sheltered spot, but a hard frost kills it — so in colder zones it is lifted, potted, or grown as a tender plant. Borderline outdoors. In its mild end of USDA 9-11 (lift and store tubers in colder zones) (and sheltered UK gardens) begonia × tuberhybrida 'pin-up flame' can stay out; in colder areas it must be lifted, brought in, or treated as a frost-tender plant.

What is the minimum temperature begonia × tuberhybrida 'pin-up flame' can survive?

What hardiness zone is begonia × tuberhybrida 'pin-up flame'?

Begonia × tuberhybrida 'Pin-Up Flame' is rated USDA 9-11 (lift and store tubers in colder zones) and RHS H2 — Tender — survives a frost-free greenhouse or a very mild, sheltered spot.

Can begonia × tuberhybrida 'pin-up flame' survive winter outside?

It can live outside year-round only in the mildest, most sheltered part of USDA 9-11 (lift and store tubers in colder zones) or a frost-free UK microclimate. In colder zones, grow it in a pot you can move under cover, or lift its tubers/roots and store them frost-free over winter. A south-facing wall, free-draining soil and a dry winter position can push it a full zone hardier than the books suggest.

How do I protect begonia × tuberhybrida 'pin-up flame' from frost?

Mulch the crown or root zone deeply with bark, straw or leaf-mould before the first hard frost. Move container plants against a warm wall or into an unheated but frost-free porch or greenhouse. Fleece the top growth on the coldest nights, and keep it on the dry side — dry roots survive cold far better than wet ones. Lift dahlia-type tubers or tender crowns after the first light frost blackens the foliage and store them somewhere cool but frost-free.