Cold hardiness & minimum temperature

Is Philodendron (Philodendron hederaceum)cold hardy? Hardiness zone & min temp

Also called heartleaf philodendron, sweetheart vine.

About Philodendron

Philodendron hederaceum · also called heartleaf philodendron, sweetheart vine · tropical

Philodendron is a large genus of vining and self-heading aroids from Central and South American rainforests. The heartleaf species (P. hederaceum) is nearly as forgiving as pothos and tolerates low light well. Mildly toxic to pets.

The heartleaf philodendron (Philodendron hederaceum) is native to Mexico, the West Indies and Brazil, growing as a climbing hemiepiphyte that twines up tree trunks in tropical forest and trails across the forest floor.

A fast trailing/climbing vine reaching about 6 m (20 ft) in habitat but commonly around 1.2 m (4 ft) indoors; tender and frost-sensitive. ASPCA classifies philodendron as toxic to cats and dogs (insoluble calcium oxalate).

Cold limit: USDA 10-12 (indoor-only) · RHS H1b (18-27°C)

Watch for — Stalled growth: Light or temperature too low — most species pause below 18°C.

Sources: missouribotanicalgarden.org, powo.science.kew.org, aspca.org

What philodendron's hardiness rating actually means

Philodendron 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 10-12 (indoor-only) — 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 has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Philodendron hardiness — frequently asked questions

Is philodendron cold hardy?

Philodendron 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 can only live outside year-round in genuinely frost-free climates (roughly USDA 10-12 (indoor-only)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature philodendron can survive?

Minimum survivable temperature is roughly about 10 °C (sustained cold below this is damaging). Philodendron has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

What hardiness zone is philodendron?

Philodendron is rated USDA 10-12 (indoor-only) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can philodendron 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 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.