Care Fundamentals
Overwintering Lithops in cold, humid climates
If you live somewhere with cold, grey, damp winters, the standard advice ('keep dry, give bright light') needs adapting. Here is how.
The problem with the standard winter regime
The textbook winter for Lithops is dry, bright, and cool — habitat conditions of the southern African interior. Northern European, Pacific Northwest, and similar climates offer the cool and the dry-substrate part but not the bright, and they layer humidity on top. The combination is what causes most winter losses.
Three concrete adjustments
Reduce minimum temperature, do not chase it. A steady 8–12 °C is safer than trying to hit 5 °C with the heat off. Cold and damp together kill; cold and dry alone is fine.
Add supplemental light. A small LED grow bar running 8–10 hours at 250–350 µmol/m²/s keeps the plant photosynthesising lightly and prevents the etiolation that always follows a dark winter on a windowsill.
Ventilate. A small fan running for a few hours a day around the plants is the cheapest single intervention. Air movement breaks the boundary layer of humid air against the body, where mould starts.
Watering during the rest
Winter-rainfall species (L. optica, L. herrei, L. ruschiorum) take small drinks through winter and rest in summer; the rest of the genus is dry through winter.
For the dry-resting majority, one very small mist on the substrate (not the body) every 4–6 weeks is enough if the air is exceptionally dry indoors. Do not water on the assumption you are 'being kind' — winter rot is the single most common cause of grower losses in this climate.
Frequently asked questions
- Will a heated propagator help?
- Sometimes — it can raise the substrate temperature enough to keep root activity ticking. But it raises humidity inside the cover, which is the opposite of what you want. Vent aggressively.
- Can I overwinter outdoors in a cold frame?
- Yes if you can keep it above 0 °C and well-ventilated. Lithops tolerate brief light frost in habitat; sustained freezing kills them.
- What about south-facing greenhouses?
- Ideal, if heated minimally and ventilated on bright days. The combination of light and ventilation handles humidity for you.
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Written by the Editorial Team. Spotted an error or want to add a regional note? Send corrections or apply to contribute.