Houseplants in winter: light and watering

In winter, light, temperature and watering are linked. Here’s how to adapt houseplant care to the species and the actual conditions in the room.

As the days grow shorter, a houseplant does not necessarily follow the same rhythm as it does in summer. Light levels fall, growth may slow and heating changes the conditions in the room. To help it get through the winter, it is best to adjust its position, watering and temperature together, taking account of the species and the home.

Move the pot towards the light

In winter, the first change is often the duration and intensity of natural light. A plant placed at the back of a room in summer may not get enough light as the days grow shorter. The Royal Horticultural Society (RHS) recommends moving some plants to a brighter spot during this season. The move should still be tailored to their needs: plants do not all tolerate direct sunlight in the same way, even behind a window.

Light and warmth go hand in hand. In a warm but poorly lit spot, a plant may produce weak, spindly growth. Conversely, a cold window or draught can expose leaves to temperature fluctuations. It is therefore useful to assess the spot itself: available light, proximity to the window, curtains closed at night, a radiator or a door that is frequently opened.

A good compromise is to find a bright spot without placing the foliage against a cold window or putting the pot directly above a radiator. Needs vary by species: a cold-sensitive tropical plant will not respond in the same way as one that can tolerate a cooler room. The plant label or a guide to its species can help you check its requirements.

Water according to the condition of the pot, not the calendar

Lower light levels and slower growth can reduce water needs. But “water less in winter” does not mean letting the potting mix dry out completely as a matter of course. How often to water depends on the plant, the growing medium, the pot size, the temperature and the humidity in the room. A heated, dry home does not create the same conditions as a cool room.

Before watering, check the potting mix rather than relying on a weekly routine. The RHS advises watering when the surface of the growing medium has dried out. With a little practice, the weight of the pot can also provide a guide: a lighter pot has generally lost more water. These clues do not replace the specific needs of the species, but they help prevent automatic watering.

Drainage matters as much as the amount of water poured in. Roots need air; if a pot sits in water for a long time, they may be deprived of it. After watering, let the excess drain away and empty the saucer. If you use a decorative outer pot, check that it is not holding water at the bottom: the RHS recommends checking the container about ten minutes after watering and removing any water that has collected.

The room temperature also affects how quickly the potting mix dries. A pot in a cool room will often need watering less frequently than the same pot in a warm room. Rather than applying the same amount or interval to all your plants, keep an eye on their growing medium and position.

Keep plants away from extremes of heating

A radiator, fireplace or hot-air vent can dry out or damage leaves. But a very cold windowsill, a draught or the space between the window and closed curtains can also cause problems. In winter, the aim is therefore not simply to keep plants warm: it is to avoid sudden temperature changes and choose a spot suited to the species.

Heating can also dry out the air. Some plants with fine leaves, as well as ferns, prefer a more humid atmosphere, the RHS says. Grouping plants together or placing them on a tray of damp pebbles can help create a more humid local environment, provided the bottom of the pot is not left submerged. This does not replace appropriate watering and may not suit every species.

If a plant spends the summer outdoors, bringing it back inside requires particular care. France Bleu Occitanie’s gardening advice recommends a gradual transition, for example by spending a few days in a cooler intermediate location before moving it into a heated room. The timing and locations mentioned in this advice relate to the Midi toulousain region: they are not a universal rule. In each case, the difference between outdoor and indoor temperatures, as well as the plant’s sensitivity, should be taken into account.

Clean the leaves and watch for changes

Dust on the foliage can hinder the light reaching the leaves. France Bleu Occitanie advises cleaning them with a damp cloth. Do this gently, and avoid treating all plants in the same way if their foliage is delicate or unusual. Take the opportunity to look at the undersides of the leaves and the stems: spotting a change or an insect early lets you monitor the plant without jumping too quickly to a specific conclusion.

A yellowed or fallen leaf is not, on its own, enough to diagnose the cause. Light, water, temperature or adjustment to a new position may all play a part. If several signs appear or the plant’s condition worsens, first examine its growing conditions and the known needs of the species before changing both watering and position at the same time.

An adjustment, not the same routine for everyone

To prepare your plants for winter, a few checks are more useful than a fixed calendar: is the room bright enough? Does the pot dry out before the next watering? Does the water drain properly? Is the plant exposed to a radiator, a draught or a cold window? These questions help you adapt your care to the actual conditions in your home.

The season changes growing conditions, but it does not make all plants the same. Watering less when growth slows, seeking more light and avoiding direct sources of heat or cold are general guidelines. You can then fine-tune the routine by observing the pot, the plant and the room.