Cold hardiness & minimum temperature

Is Teague's Porroglossum (Porroglossum teaguei)cold hardy? Hardiness zone & min temp

Also called Teague's Porroglossum.

More about teague's porroglossum

About Teague's Porroglossum

Porroglossum teaguei · also called Teague's Porroglossum · tropical

A miniature, cold-growing epiphyte or terrestrial from Pichincha province, Ecuador at around 2,200 m, named for its discoverer Walter Teague. It bears translucent, bright-purple flowers with long tails on successive spikes that bloom in spring. Its sensitive, fine root system requires cool conditions, consistent but well-draining moisture, and shade.

Cold limit: USDA 11–12 · RHS H1a (9–18°C (day); nights 9–13°C)

Watch for — Root death from temperature extremes: Temperatures above 22°C cause rapid deterioration of the fine root system. Ensure the growing space stays within 9–18°C at all times. In a cool greenhouse, double-potting with a damp outer pot helps buffer root-zone temperature on unexpectedly warm days.

What teague's porroglossum's hardiness rating actually means

Teague's Porroglossum 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 H1a means: Tropical — needs a heated room or greenhouse; no frost tolerance whatsoever. On the US scale that maps to USDA 11–12 — 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 above about 15 °C (warm, never cold). Teague's Porroglossum has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for teague's porroglossum as it gets too cold:

Below about above about 15 °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 teague's porroglossum go outside or overwinter — and where?

It can holiday outdoors in summer once nights are reliably above above 15 °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 teague's porroglossum can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1a figure above.

Teague's Porroglossum hardiness — frequently asked questions

Is teague's porroglossum cold hardy?

Teague's Porroglossum 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. Teague's Porroglossum can only live outside year-round in genuinely frost-free climates (roughly USDA 11–12); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature teague's porroglossum can survive?

Minimum survivable temperature is roughly above about 15 °C (warm, never cold). Teague's Porroglossum has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

What hardiness zone is teague's porroglossum?

Teague's Porroglossum is rated USDA 11–12 and RHS H1a — Tropical — needs a heated room or greenhouse; no frost tolerance whatsoever.

Can teague's porroglossum survive winter outside?

It can holiday outdoors in summer once nights are reliably above above 15 °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 teague's porroglossum below its minimum temperature?

Below about above about 15 °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.