Caring for Houseplants in Winter

Houseplants have different care needs in winter because natural growth stagnates due to the lack of daylight. For many plant owners this is a period when care requires closer attention, as the standard summer routine often leads to problems. It is necessary to adjust the watering and location of your plants to the changing indoor conditions. This blog contains a number of tips so that you can take optimal care of your houseplant during the winter!

Watering houseplants in winter

The most common mistake in winter is sticking to the summer watering schedule. Because the sun is less powerful and the days are shorter, houseplants consume significantly less water. Evaporation through the leaves is at a low level. When you overwater, the potting soil at the bottom of the pot remains saturated, preventing the roots from receiving oxygen and causing them to rot. Therefore, always check the soil manually before reaching for the watering can. Stick your finger at least two to three centimeters deep into the soil. Does it still feel moist? Then feel free to wait a few days. For many species, such as the Monstera or the Sansevieria, it is even better in winter to let the soil dry out almost completely before watering again. Moreover, always use water at room temperature; ice-cold tap water can literally give the roots of tropical plants a cold shock.

Houseplant humidity in winter

In winter, indoor humidity often drops to an all-time low, sometimes even below 30%. For most tropical houseplants, which are accustomed to humidity levels of 60% to 80%, this is extremely stressful. You can recognize low humidity by brown, crackling leaf edges or leaves that fall off prematurely. To compensate for this, you can take various measures. Simply spraying the leaves with a plant sprayer often has only a short-term effect. Grouping plants is more effective, so that they create a microclimate together with a higher humidity level. Placing bowls of water and hydro granules under the pot (ensuring the pot does not touch the bottom of the bowl) or hanging water trays on the radiator also helps to make the air less dry locally.

What effect does heating have on your houseplants?

Central heating is one of the biggest challenges for houseplants in winter. Radiators spread a constant stream of warm, dry air. If a plant stands directly above or next to an active radiator, moisture evaporates from the leaves faster than the roots can supply it. This process exhausts the plant rapidly. In addition, the heating causes large temperature differences. While the top of the plant is in the warm airflow, the bottom can rest on a cold windowsill. These temperature fluctuations make the plant susceptible to stress and attract pests, such as spider mites, which thrive in warm, dry conditions. If possible, it is better to place plants a meter away from the radiator on a slight elevation in the winter.

Does your plant need plant food in the winter?

The short answer is: no. Plant food is intended to support active growth. However, in the winter, most houseplants are dormant and produce hardly any new cells. The minerals and salts in the fertilizer are not absorbed by the roots and accumulate in the potting soil.

This accumulation can damage the roots, a process we call root burn. Paradoxically, this actually causes the plant to absorb less water. Only when you see the first new light green leaves appear in early spring (often around March) is it time to very slowly build up the fertilizer again. Until then, good quality potting soil contains more than enough reserves to get through the winter.

Repotting houseplants in winter

Although you might be tempted to put your plants in a larger plant pot during a free winter day, this is not advisable. When repotting, microscopic cracks inevitably form in the roots. In the summer, a plant recovers from this within a few days, but in the winter, the plant lacks the energy and sap flow to heal these wounds. The damaged roots are an easy target for fungi in cold, damp soil. Moreover, the plant will not immediately utilize the new space in the pot during the winter, causing the extra soil to remain wet for longer. It is better to wait until spring, when the longer days give the plant the necessary growth vigor to root immediately in its new pot.

Do plants go into hibernation?

From a biological point of view, the term 'hibernation' is not entirely correct for houseplants; we prefer to speak of a rest period or dormancy. Unlike many outdoor plants that lose their leaves, most houseplants remain green, but their internal engine runs at a very low speed. This is directly controlled by the amount of light.

Because there are simply not enough light particles to produce sufficient sugars through photosynthesis, the plant chooses to halt growth. This is a survival strategy. Some plants, such as the Alocasia or the Caladium, can even die back completely above ground to emerge again from the tuber in the spring. It is important to respect this rest and not force the plant to grow with extra water or heat.

Why do my houseplants die in the winter?

The main reason for plant mortality in the winter is a combination of 'overcare' and a lack of light. Plant owners see the plant deteriorating and think that more water or extra nutrients is the solution. In reality, this exacerbates the situation: the roots drown and rot away. A plant without healthy roots can no longer transport water, causing the leaves to droop, which is often mistakenly perceived as drought. In addition, weakened plants are susceptible to pests. Spider mites, thrips, and mealybugs spread quickly in the dry air of our living rooms. Because the plant is dormant, it has less resistance to defend itself against this attack. A weekly check on the underside of the leaves is therefore not an unnecessary luxury in winter. Optimal daylight for plants in winter Because the sun is much lower in the sky in winter and the days are significantly shorter, the light output indoors is sometimes as much as 50% to 80% lower than in summer. For a plant, every centimeter of distance from the window counts. A plant that stands two meters from the window in the summer often does not receive enough energy to survive in the winter. Therefore, move your plants as close to the glass as possible in the winter. A south-facing location is ideal now, because the sun is not strong enough to burn the leaves. However, be careful with single glazing or very cold nights; the cold coming from the window can damage the plant. Additionally, keep the leaves dust-free with a damp cloth; After all, a layer of dust blocks the few light rays that still reach the plant.

Successfully caring for houseplants in winter revolves around observation and restraint. By respecting the natural dormancy period and subtly adjusting environmental factors such as light and humidity, you ensure that your plants start the new growing season strong and healthy.