Cold hardiness & minimum temperature

Is Tina butterwort (Pinguicula 'Tina')cold hardy? Hardiness zone & min temp

Also called Tina butterwort, Tina Mexican butterwort.

More about tina butterwort

About Tina butterwort

Pinguicula 'Tina' · also called Tina butterwort, Tina Mexican butterwort · houseplant

Pinguicula 'Tina' (P. agnata × P. zecheri) is one of the most beginner-friendly Mexican butterwort hybrids, forming a flat rosette of lime-green glistening leaves that trap fungus gnats year-round. It blooms prolifically with pale lavender flowers and undergoes a compact succulent winter phase rather than true dormancy.

Cold limit: USDA 10-12 · RHS H1b (15–25°C year-round; can tolerate brief dips to 10°C)

Watch for — Crown rot from overwatering in winter: The most common cause of death. When the plant shifts to its small succulent winter leaves, its water requirements drop dramatically. Continue watering as in summer and the crown rots within weeks. Reduce watering sharply once you notice the shift to smaller, non-sticky leaves.

What tina butterwort's hardiness rating actually means

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

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

Tina butterwort hardiness — frequently asked questions

Is tina butterwort cold hardy?

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

What is the minimum temperature tina butterwort can survive?

What hardiness zone is tina butterwort?

Tina butterwort is rated USDA 10-12 and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can tina 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 tina 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.