Cold hardiness & minimum temperature

Is Hygrophila lancea 'Araguaia' (Hygrophila lancea 'Araguaia')cold hardy? Hardiness zone & min temp

Also called Araguaia hygro, lance hygrophila.

More about hygrophila lancea 'araguaia'

About Hygrophila lancea 'Araguaia'

Hygrophila lancea 'Araguaia' · also called Araguaia hygro, lance hygrophila · tropical

A fully submerged aquarium stem plant prized for narrow lance-shaped leaves that flush coppery-red to purple under strong light. A mid-to-background aquascaping plant, it rewards high-tech tanks with CO2 injection and rich substrate, growing compact and bushy. Slower than most hygrophilas, it stays manageable but needs stable parameters to hold its colour.

Cold limit: USDA Not applicable (tropical aquarium plant grown indoors in heated water) (22-28°C)

What hygrophila lancea 'araguaia''s hardiness rating actually means

Hygrophila lancea 'Araguaia' 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 Not applicable (tropical aquarium plant grown indoors in heated water) — 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). Hygrophila lancea 'Araguaia' has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Hygrophila lancea 'Araguaia' hardiness — frequently asked questions

Is hygrophila lancea 'araguaia' cold hardy?

Hygrophila lancea 'Araguaia' 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. Hygrophila lancea 'Araguaia' can only live outside year-round in genuinely frost-free climates (roughly USDA Not applicable (tropical aquarium plant grown indoors in heated water)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature hygrophila lancea 'araguaia' can survive?

What hardiness zone is hygrophila lancea 'araguaia'?

Hygrophila lancea 'Araguaia' is rated USDA Not applicable (tropical aquarium plant grown indoors in heated water) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can hygrophila lancea 'araguaia' 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 hygrophila lancea 'araguaia' 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.