Cold hardiness & minimum temperature

Is Philodendron 'Ring of Fire' (Philodendron 'Ring of Fire')cold hardy? Hardiness zone & min temp

Also called Ring of Fire Philodendron, Philodendron Ring of Fire, Ring of Fire.

More about philodendron 'ring of fire'

About Philodendron 'Ring of Fire'

Philodendron 'Ring of Fire' · also called Ring of Fire Philodendron, Philodendron Ring of Fire · tropical

Philodendron 'Ring of Fire' is a rare, slow-growing climbing aroid hybrid prized for serrated leaves that emerge orange-red and mature to cream, green and pink variegation. It wants bright indirect light, high humidity and a moss pole. Toxic to cats and dogs (insoluble calcium oxalate crystals) per the ASPCA.

Cold limit: USDA 9b-11 (grown as a houseplant elsewhere) (18-29 C)

What philodendron 'ring of fire''s hardiness rating actually means

Philodendron 'Ring of Fire' 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 9b-11 (grown as a houseplant elsewhere) — 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). Philodendron 'Ring of Fire' has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for philodendron 'ring of fire' 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 philodendron 'ring of fire' 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 philodendron 'ring of fire' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1b figure above.

Philodendron 'Ring of Fire' hardiness — frequently asked questions

Is philodendron 'ring of fire' cold hardy?

Philodendron 'Ring of Fire' 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. Philodendron 'Ring of Fire' can only live outside year-round in genuinely frost-free climates (roughly USDA 9b-11 (grown as a houseplant elsewhere)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature philodendron 'ring of fire' can survive?

What hardiness zone is philodendron 'ring of fire'?

Philodendron 'Ring of Fire' is rated USDA 9b-11 (grown as a houseplant elsewhere) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can philodendron 'ring of fire' 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 philodendron 'ring of fire' 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.