Cold hardiness & minimum temperature

Is Double Angel's Trumpet (Brugmansia suaveolens 'Plena')cold hardy? Hardiness zone & min temp

Also called Double Angel's Trumpet, Double White Angel's Trumpet, Plena Brugmansia.

More about double angel's trumpet

About Double Angel's Trumpet

Brugmansia suaveolens 'Plena' · also called Double Angel's Trumpet, Double White Angel's Trumpet · flowering

Brugmansia suaveolens 'Plena' is a cultivar of the Brazilian angel's trumpet, notable for its spectacular double or semi-double pendulous white trumpets with an intensely sweet evening fragrance. It grows vigorously and flowers prolifically from summer through autumn. All parts are severely toxic. An impressive patio or conservatory specimen.

Cold limit: USDA 10–12 · RHS H1c (10–32°C)

Watch for — Spider mites in winter storage: Overwintered plants in warm, dry conditions are very susceptible to spider mite; inspect weekly under leaves and treat at first sign with neem oil or insecticidal soap, increasing humidity around the plant.

What double angel's trumpet's hardiness rating actually means

Double Angel's Trumpet 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 10–12 — 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). Double Angel's Trumpet has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for double angel's trumpet 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 double angel's trumpet 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 double angel's trumpet can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1c figure above.

Double Angel's Trumpet hardiness — frequently asked questions

Is double angel's trumpet cold hardy?

Double Angel's Trumpet 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. Double Angel's Trumpet can only live outside year-round in genuinely frost-free climates (roughly USDA 10–12); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature double angel's trumpet can survive?

Minimum survivable temperature is roughly about 5 °C (and never frost). Double Angel's Trumpet has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

What hardiness zone is double angel's trumpet?

Double Angel's Trumpet is rated USDA 10–12 and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can double angel's trumpet 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 double angel's trumpet 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.