Cold hardiness & minimum temperature

Is Climbing Aloe (Aloe ciliaris)cold hardy? Hardiness zone & min temp

Also called Climbing aloe, Common climbing aloe.

More about climbing aloe

About Climbing Aloe

Aloe ciliaris · also called Climbing aloe, Common climbing aloe · houseplant

Aloe ciliaris (now often placed in Aloiampelos) is the climbing aloe, a fast-growing scrambling species from South Africa's Eastern Cape. Its slender, flexible stems are clothed in soft, recurved leaves with tiny white marginal hairs (cilia) that help it lean and clamber through surrounding shrubs. It flowers freely over a long season with tubular orange-red blooms, making it a vigorous, easy aloe.

Cold limit: USDA 9-11 (tender; protect from frost) · RHS H1c (10-30°C)

Watch for — Frost damage: Tender to frost; stems are damaged by hard cold. Shelter or overwinter indoors in cold regions.

What climbing aloe's hardiness rating actually means

Climbing Aloe 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 9-11 (tender; protect from frost) — 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). Climbing Aloe has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for climbing aloe 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 climbing aloe 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 climbing aloe can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1c figure above.

Climbing Aloe hardiness — frequently asked questions

Is climbing aloe cold hardy?

Climbing Aloe 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. Climbing Aloe can only live outside year-round in genuinely frost-free climates (roughly USDA 9-11 (tender; protect from frost)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature climbing aloe can survive?

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

What hardiness zone is climbing aloe?

Climbing Aloe is rated USDA 9-11 (tender; protect from frost) and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can climbing aloe 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 climbing aloe 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.