Cold hardiness & minimum temperature

Is Hoya Compacta 'Regalis' (Hoya compacta 'Regalis')cold hardy? Hardiness zone & min temp

Also called Variegated Hindu Rope Plant.

More about hoya compacta 'regalis'

About Hoya Compacta 'Regalis'

Hoya compacta 'Regalis' · also called Variegated Hindu Rope Plant · houseplant

Hoya compacta 'Regalis' is a variegated Hindu rope plant: thick, curled and twisted leaves edged in creamy white pack densely along ropey, cascading stems. It is slow-growing and quirky, producing fragrant pink star-flower clusters. The crinkled, crevice-filled leaves trap water and pests, so it rewards careful watering and bright light.

Cold limit: USDA 10-12 (indoor in most US homes) · RHS H1b (18-27°C)

Watch for — Overwatering: Its highly succulent leaves make it very drought-tolerant, so frequent watering rots the roots. Let the mix dry well between drinks and keep it lean, especially in winter.

What hoya compacta 'regalis''s hardiness rating actually means

Hoya Compacta 'Regalis' 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 US homes) — 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). Hoya Compacta 'Regalis' has no frost tolerance at all — it is an indoor plant in any climate with a real winter.

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

Hoya Compacta 'Regalis' hardiness — frequently asked questions

Is hoya compacta 'regalis' cold hardy?

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

What is the minimum temperature hoya compacta 'regalis' can survive?

What hardiness zone is hoya compacta 'regalis'?

Hoya Compacta 'Regalis' is rated USDA 10-12 (indoor in most US homes) and RHS H1b — Sub-tropical — a normal warm home is fine, but it cannot go outside in a cool season.

Can hoya compacta 'regalis' 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 hoya compacta 'regalis' 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.