Houseplants in winter: less light, dry air
From November to February a plant on the windowsill often receives only a tenth of the light it gets in summer. At the same time, humidity in heated rooms drops to 30 % and below. Yet most houseplants come from tropical forests with evenly high humidity. No wonder leaves turn yellow, tips dry out and spider mites appear now.
The good news: adapting care to the season gets almost every plant through winter without losses. Five adjustments make the difference.
- Light
- As close to the window as possible; south-facing windows are ideal now.
- Watering
- Less often but thoroughly – only when the top of the soil is dry.
- Humidity
- Bowls of water, group plants, never above the radiator.
- Temperature
- No cold draughts when airing, no leaves touching the glass.
Light: the most important factor
Plants that stood a metre from the window in summer now move right up to the glass. A south-facing window that would be too hot in July is the best spot in the house in January. Dust on the leaves swallows extra light – so wipe large-leaved species such as the fiddle-leaf fig with a damp cloth once a month.
Turning helps too: a quarter turn per week stops the plant from growing lopsided towards the light.
Watering: less is more
Water consumption falls with the light. Watering in winter as in summer risks waterlogging and rotting roots – the most common reason houseplants die in winter. The finger test is more reliable than any fixed schedule: only water when the top two to three centimetres of soil are dry.
| Plant | Watering in winter | Minimum temperature | Special note |
|---|---|---|---|
| Monstera | every 10–14 days | 16 °C | Do not cut aerial roots |
| Fiddle-leaf fig | every 10 days | 15 °C | Do not move it |
| Snake plant | every 4 weeks | 12 °C | tolerates drought |
| Lemon tree | weekly, a little | 5 °C | bright and cool |
If you want to be completely sure, measure: a soil moisture sensor shows on your smartphone when the root ball is actually dry.
Humidity and pests
Dry heated air favours spider mites and thrips. First signs are fine, pale speckles on the leaves and delicate webs in the leaf axils. Preventive measures:
- Group plants together – they raise humidity for each other
- Place shallow trays of water and pebbles under the pots
- Mist the leaves with low-lime, room-temperature water
- Shower affected plants and separate them from the others
More houseplants die from too much care in winter than from too little.
Rule of thumb from the nursery
No feeding, no repotting
Without enough light a plant cannot use nutrients; fertiliser then builds up in the substrate and damages the roots. So do not feed from October to February. Repotting can also wait until March, when the days get longer again and new growth begins.
Robust plants for bright rooms
Usually because it was moved, a cold draught or soil that is too wet. Put the plant in a bright, draught-free spot and leave it there.
Yes. An LED grow light running 10–12 hours a day reliably compensates for dark spots.
Only in an emergency, for example root rot. Otherwise wait until March.
