Growli

UK temperature

Keeping day-blooming jasmine warm in a UK home

Cestrum diurnum

RHS H2USDA 9-11Toxic to pets

More about day-blooming jasmine in the UK

The UK home, in plant terms

A typical UK home creates two opposite micro-problems at the same time. Radiator-driven heating spikes the air temperature and crashes humidity in the rooms where people actually sit; the older the housing stock the more likely a single-glazed window pane is sitting at near-freezing in January with a houseplant against it. Cold unheated bedrooms, north-facing rooms and conservatories without heating run far cooler than the thermostat suggests, and the British winter gives the lowest indoor daylight in any of Growli's markets. Day-blooming Jasmine is frost-tender, so the radiator-warmed side of the house is right for it in winter — just not pressed against a cold pane or directly in the radiator updraft.

The actual numbers

Ideally day-blooming jasmine sits between 10–35°C. (That is 50–95°F in Fahrenheit.) Naturally adapted to humid subtropical and tropical climates. Tolerates moderate humidity in cultivation. In very dry conditions or heated indoor environments, occasional misting or use of a humidity tray helps prevent leaf edge browning. Performs well outdoors in humid regions without supplemental moisture. Watch for the room dropping below about 10°C overnight — common in UK unheated bedrooms in January, and the point where growth stalls and leaves chill-mark.

For the RHS hardiness side of this, see is day-blooming jasmine hardy in the UK? (rating RHS H2, sourced from the RHS rating system). For the US/USDA framing of the same numbers, see the day-blooming jasmine temperature guide.

Winter placement in a UK home

For day-blooming jasmine through a UK winter, three placement rules clear up most problems: 1) keep it at least a hand's width back from the window pane on single-glazed or very cold double-glazed glass, especially overnight when curtains close behind the plant; 2) keep it out of the direct vertical updraft above a radiator — that column of hot dry air browns leaf tips even on tolerant species; 3) judge by the room you can actually feel, not the central thermostat — many UK rooms run several degrees below the hall reading in winter. Humidity drops to roughly 25–35% in a heated UK living room; a pebble tray, grouping with other plants, or a small humidifier puts that back to a level houseplants actually like.

Day-blooming Jasmine temperature in the UK — frequently asked questions

What temperature does day-blooming jasmine need in the UK?

Day-blooming Jasmine prefers 10–35°C (50–95°F). The British issue is rarely the average — it is the extremes: a cold single-glazed window in January, the hot dry air directly above a radiator, or a north-facing unheated room that runs far cooler than the hall thermostat.

Will day-blooming jasmine survive a cold UK winter room?

Day-blooming Jasmine is frost-tender (RHS H2). Keep it well above freezing, ideally above 10°C overnight, which means the radiator-warmed side of the house rather than an unheated bedroom or conservatory.

Can day-blooming jasmine go on a UK windowsill in winter?

On a single-glazed or very cold pane, no — overnight the leaves pressed against the glass can drop below the plant's comfort band, especially behind drawn curtains. A small gap (a hand's width back) or thicker thermal curtains in front of the plant fixes it, and modern double-glazing usually solves it outright.

Does UK radiator-driven heating dry day-blooming jasmine out?

Yes — UK living rooms typically run at around 25–35% relative humidity in winter. That is well below what most houseplants prefer. Day-blooming Jasmine tolerates this better than the calathea-and-fern family, but a pebble tray or grouping plants still helps.

What temperature range does day-blooming jasmine actually like?

10–35°C is the comfortable band (50–95°F in Fahrenheit for reference). That covers normal UK living-room temperatures all year; the work is making sure cold pockets (windowsills, unheated rooms) and hot pockets (radiator updrafts) do not push it outside that band.

More day-blooming jasmine care

See the full day-blooming jasmine care guide, its UK watering (hard vs soft tap water), and UK hardiness.