Cold hardiness & minimum temperature

Is Aeschynanthus speciosus (Aeschynanthus speciosus)cold hardy? Hardiness zone & min temp

Also called orange lipstick plant, showy lipstick vine.

More about aeschynanthus speciosus

About Aeschynanthus speciosus

Aeschynanthus speciosus · also called orange lipstick plant, showy lipstick vine · flowering

Aeschynanthus speciosus is one of the showiest lipstick plants, producing dense terminal clusters of large orange-and-yellow tubular flowers above trailing stems of glossy green leaves. This epiphytic gesneriad blooms generously in summer given bright indirect light, warmth and humidity. Grow it in an airy mix in a hanging basket, keeping roots evenly moist but never waterlogged.

Cold limit: USDA 10-11 (indoor in most US homes) · RHS H1b (18-27°C)

Watch for — Bud drop before opening: Caused by dry air, inconsistent watering, or temperature swings during budding. Keep humidity up, water steadily, and avoid moving the plant once buds form.

What aeschynanthus speciosus's hardiness rating actually means

Aeschynanthus speciosus 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 (indoor 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). Aeschynanthus speciosus has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Aeschynanthus speciosus hardiness — frequently asked questions

Is aeschynanthus speciosus cold hardy?

Aeschynanthus speciosus 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. Aeschynanthus speciosus can only live outside year-round in genuinely frost-free climates (roughly USDA 10-11 (indoor in most US homes)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature aeschynanthus speciosus can survive?

What hardiness zone is aeschynanthus speciosus?

Aeschynanthus speciosus is rated USDA 10-11 (indoor 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 aeschynanthus speciosus 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 aeschynanthus speciosus 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.