Cold hardiness & minimum temperature

Is Tropical Dewy Pine (Drosophila indica)cold hardy? Hardiness zone & min temp

Also called tropical dewy pine, Indian sundew, tropical sundew.

More about tropical dewy pine

About Tropical Dewy Pine

Drosophila indica · also called tropical dewy pine, Indian sundew · houseplant

A fast-growing annual tropical sundew from Australia, India, and Southeast Asia, producing upright stems to 30 cm clothed in long, glandular leaves that glitter like dewdrops — inspiring the common name. Thrives in very bright, warm, humid conditions. Unlike temperate sundews it needs no dormancy, growing year-round in a warm windowsill or terrarium from seed.

Cold limit: USDA 10–12 (frost-sensitive; treated as an annual in temperate climates) · RHS H1a (18–38°C)

What tropical dewy pine's hardiness rating actually means

Tropical Dewy Pine 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 10–12 (frost-sensitive; treated as an annual in temperate 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 above about 15 °C (warm, never cold). Tropical Dewy Pine has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for tropical dewy pine 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 tropical dewy pine 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 tropical dewy pine can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1a figure above.

Tropical Dewy Pine hardiness — frequently asked questions

Is tropical dewy pine cold hardy?

Tropical Dewy Pine 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. Tropical Dewy Pine can only live outside year-round in genuinely frost-free climates (roughly USDA 10–12 (frost-sensitive; treated as an annual in temperate climates)); everywhere else it is a houseplant that summers out at most.

What is the minimum temperature tropical dewy pine can survive?

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

What hardiness zone is tropical dewy pine?

Tropical Dewy Pine is rated USDA 10–12 (frost-sensitive; treated as an annual in temperate climates) and RHS H1a — Tropical — needs a heated room or greenhouse; no frost tolerance whatsoever.

Can tropical dewy pine 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 tropical dewy pine 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.