Cold hardiness & minimum temperature

Is Red Aloe (Aloe cameronii)cold hardy? Hardiness zone & min temp

Also called Red aloe, Cameron's aloe.

More about red aloe

About Red Aloe

Aloe cameronii · also called Red aloe, Cameron's aloe · houseplant

Aloe cameronii is the red aloe, an East African species famous for foliage that turns deep coppery red to mahogany when grown in full sun and given a controlled dry spell. It forms sprawling, branching clumps of slender, curved leaves and sends up orange-red flower spikes in autumn and winter. Easy, fast for an aloe, and one of the most colourful.

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

Watch for — Frost damage: Tender to frost; foliage is damaged in hard cold. Shelter or move indoors over winter in cold regions.

What red aloe's hardiness rating actually means

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

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

Red Aloe hardiness — frequently asked questions

Is red aloe cold hardy?

Red 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. Red 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 red aloe can survive?

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

What hardiness zone is red aloe?

Red 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 red 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 red 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.