Cold hardiness & minimum temperature

Is Pilea glauca 'Aquamarine' (Grey Baby Tears) (Pilea glauca)cold hardy? Hardiness zone & min temp

Also called Grey baby tears, Aquamarine pilea, Silver sparkle pilea, Grey artillery plant, Pilea libanensis.

More about pilea glauca 'aquamarine' (grey baby tears)

About Pilea glauca 'Aquamarine' (Grey Baby Tears)

Pilea glauca · also called Grey baby tears, Aquamarine pilea · houseplant

Pilea glauca 'Aquamarine', or grey baby tears, is a delicate trailing houseplant prized for its tiny blue-grey leaves on wiry red stems. Give it bright indirect light, evenly moist (never soggy) soil and warmth above 10C. It loves humidity and terrariums. ASPCA-clean genus, so it is treated as pet-safe.

Cold limit: USDA 10-12 (a tender tropical grown as a houseplant in cooler climates; not frost-hardy) (18-26C)

Watch for — Crispy edges and leaf drop: Usually low humidity or the soil drying out fully. Raise humidity (pebble tray, humidifier, terrarium) and keep moisture even, especially in heated winter rooms.

What pilea glauca 'aquamarine' (grey baby tears)'s hardiness rating actually means

Pilea glauca 'Aquamarine' (Grey Baby Tears) 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 10-12 (a tender tropical grown as a houseplant in cooler climates; not frost-hardy) — 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). Pilea glauca 'Aquamarine' (Grey Baby Tears) has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for pilea glauca 'aquamarine' (grey baby tears) 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 pilea glauca 'aquamarine' (grey baby tears) 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 pilea glauca 'aquamarine' (grey baby tears) can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1c figure above.

Pilea glauca 'Aquamarine' (Grey Baby Tears) hardiness — frequently asked questions

Is pilea glauca 'aquamarine' (grey baby tears) cold hardy?

Pilea glauca 'Aquamarine' (Grey Baby Tears) 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. Pilea glauca 'Aquamarine' (Grey Baby Tears) can only live outside year-round in genuinely frost-free climates (roughly USDA 10-12 (a tender tropical grown as a houseplant in cooler climates; not frost-hardy)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature pilea glauca 'aquamarine' (grey baby tears) can survive?

What hardiness zone is pilea glauca 'aquamarine' (grey baby tears)?

Pilea glauca 'Aquamarine' (Grey Baby Tears) is rated USDA 10-12 (a tender tropical grown as a houseplant in cooler climates; not frost-hardy) and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can pilea glauca 'aquamarine' (grey baby tears) 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 pilea glauca 'aquamarine' (grey baby tears) 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.