Cold hardiness & minimum temperature

Is Ibarra's Butterwort (Pinguicula ibarrae)cold hardy? Hardiness zone & min temp

Also called Ibarra's butterwort, Ibarrae butterwort.

More about ibarra's butterwort

About Ibarra's Butterwort

Pinguicula ibarrae · also called Ibarra's butterwort, Ibarrae butterwort · tropical

Pinguicula ibarrae is a Mexican butterwort first collected from foggy limestone cliff faces near Tlanchinol, Hidalgo, where humidity stays high year-round. Unlike many Mexican Pinguicula, it rarely enters a full succulent dormancy and tends to retain its broad, strap-shaped carnivorous leaves even through drier periods, making it one of the more forgiving Mexican species to cultivate. Grow it in a loose, alkaline, mineral-rich mix and provide bright indirect light; never use tap water high in minerals. Neither Pinguicula ibarrae nor the genus Pinguicula appears on the ASPCA Toxic & Non-Toxic Plants list — the genus is not a recognised toxic group — however, the sticky digestive mucilage could cause mild gastric upset if ingested; classify as mildly-toxic until an authoritative listing confirms safety.

Cold limit: USDA 10-12 (indoor in most climates) · RHS H1b (13–28°C)

What ibarra's butterwort's hardiness rating actually means

Ibarra's Butterwort 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 in most climates) — 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). Ibarra's Butterwort has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Ibarra's Butterwort hardiness — frequently asked questions

Is ibarra's butterwort cold hardy?

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

What is the minimum temperature ibarra's butterwort can survive?

What hardiness zone is ibarra's butterwort?

Ibarra's Butterwort is rated USDA 10-12 (indoor in most climates) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can ibarra's butterwort 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 ibarra's butterwort 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.