UK temperature
Keeping rough-leaved cape mallow warm in a UK home
Anisodontea scabrosa
More about rough-leaved cape mallow 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. Rough-leaved Cape Mallow tolerates a wider band, but the worst-case UK winter placement (a cold single-glazed pane plus a hot dry radiator below it) still stresses it through repeated drying and chilling.
The actual numbers
Ideally rough-leaved cape mallow sits between -3 to 32°C. (That is 27 to 90°F in Fahrenheit.) Tolerates dry conditions well once established; good air circulation around the foliage reduces the risk of fungal issues in humid conditions. Watch for the room dropping below about -3°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 rough-leaved cape mallow hardy in the UK? (rating RHS H3, sourced from the RHS rating system). For the US/USDA framing of the same numbers, see the rough-leaved cape mallow temperature guide.
Winter placement in a UK home
For rough-leaved cape mallow 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.
Rough-leaved Cape Mallow temperature in the UK — frequently asked questions
What temperature does rough-leaved cape mallow need in the UK?
Rough-leaved Cape Mallow prefers -3 to 32°C (27 to 90°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 rough-leaved cape mallow survive a cold UK winter room?
Rough-leaved Cape Mallow tolerates a wider winter band — see its RHS rating H3. Below about -3°C growth stalls; cold-wet roots, not cold air, are usually what kills it indoors.
Can rough-leaved cape mallow 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 rough-leaved cape mallow out?
Yes — UK living rooms typically run at around 25–35% relative humidity in winter. That is well below what most houseplants prefer. Rough-leaved Cape Mallow tolerates this better than the calathea-and-fern family, but a pebble tray or grouping plants still helps.
What temperature range does rough-leaved cape mallow actually like?
-3 to 32°C is the comfortable band (27 to 90°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 rough-leaved cape mallow care
See the full rough-leaved cape mallow care guide, its UK watering (hard vs soft tap water), and UK hardiness.