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Cold hardiness & minimum temperature

Is Kenneally's Sundew (Drosera kenneallyi)cold hardy? Hardiness zone & min temp

Also called Kenneally's sundew.

More about kenneally's sundew

About Kenneally's Sundew

Drosera kenneallyi · also called Kenneally's sundew · tropical

Drosera kenneallyi is a rare member of the petiolaris complex, described from limited locations in the Kimberley region of Western Australia, where it grows on seasonally inundated sandy or gravelly substrates at low altitude. It shares the characteristic monsoon-dependent lifecycle of its petiolaris relatives — growing vigorously in the warm wet season and retreating to a subterranean rhizome in the dry season. The single most important care fact is that this species is among the most heat-demanding of the complex; sustained temperatures below 20 °C at any time of year are detrimental. Drosera is not listed as toxic to cats or dogs by the ASPCA and is considered non-toxic to pets.

Cold limit: USDA 10-12 (indoor in most climates) · RHS H1b (22–40 °C (growing); 18–30 °C (rest))

Watch for — Slow or absent emergence after dormancy: If the rhizome fails to produce new growth at the start of the growing season, the most common cause is insufficient warmth — ensure temperatures are consistently above 25 °C. Briefly increase moisture to stimulate re-sprouting, then gradually transition to full wet-season watering.

What kenneally's sundew's hardiness rating actually means

Kenneally's Sundew 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 (indoor in most 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 about 10 °C (sustained cold below this is damaging). Kenneally's Sundew has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

Concretely, for kenneally's sundew as it gets too cold:

Can kenneally's sundew go outside or overwinter — and where?

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 kenneally's sundew can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1b figure above.

Kenneally's Sundew hardiness — frequently asked questions

Is kenneally's sundew cold hardy?

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

What is the minimum temperature kenneally's sundew can survive?

Minimum survivable temperature is roughly about 10 °C (sustained cold below this is damaging). Kenneally's Sundew has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

What hardiness zone is kenneally's sundew?

Kenneally's Sundew is rated USDA 10-12 (indoor in most climates) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can kenneally's sundew 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 kenneally's sundew 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.

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