Cold hardiness & minimum temperature

Is Cryptocoryne wendtii 'Green' (Cryptocoryne wendtii 'Green')cold hardy? Hardiness zone & min temp

Also called green Wendt's Crypt, wendtii green.

More about cryptocoryne wendtii 'green'

About Cryptocoryne wendtii 'Green'

Cryptocoryne wendtii 'Green' · also called green Wendt's Crypt, wendtii green · tropical

Cryptocoryne wendtii 'Green' is a hardy Sri Lankan aquatic aroid forming rosettes of olive-green, slightly textured leaves. A versatile substrate-rooted mid-ground plant, it tolerates low light and a wide water range, spreading by runners. Famous for melting after replanting, it reliably regrows once roots settle, making it a beginner aquascaping favourite.

Cold limit: USDA 11-12 (true tropical; aquarium/indoor only) · RHS H1a (22-28°C)

What cryptocoryne wendtii 'green''s hardiness rating actually means

Cryptocoryne wendtii 'Green' 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 (true tropical; aquarium/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 above about 15 °C (warm, never cold). Cryptocoryne wendtii 'Green' has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for cryptocoryne wendtii 'green' 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 cryptocoryne wendtii 'green' 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 cryptocoryne wendtii 'green' can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1a figure above.

Cryptocoryne wendtii 'Green' hardiness — frequently asked questions

Is cryptocoryne wendtii 'green' cold hardy?

Cryptocoryne wendtii 'Green' 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. Cryptocoryne wendtii 'Green' can only live outside year-round in genuinely frost-free climates (roughly USDA 11-12 (true tropical; aquarium/indoor only)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature cryptocoryne wendtii 'green' can survive?

What hardiness zone is cryptocoryne wendtii 'green'?

Cryptocoryne wendtii 'Green' is rated USDA 11-12 (true tropical; aquarium/indoor only) and RHS H1a — Tropical — needs a heated room or greenhouse; no frost tolerance whatsoever.

Can cryptocoryne wendtii 'green' 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 cryptocoryne wendtii 'green' 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.