Most of our house plants hail from tropical, subtropical, or Mediterranean areas. It is then no surprise that long winter months in heated rooms and extended periods of low sun hours can confuse our plants.
While a lot of house plants tent to go through a dormant period in winter months guided by the drop in sunny hours, the 20-23°C house temperatures would mean spring or end of summer for them.
During this stage, their natural development could turn abnormal which is often indicated through the production of weak, scruffy, and yellowish new shoots. These changes can also signify a deterioration in general health condition which could leave many plants more exposed to any potential infectious diseases or insects.
We can make this situation even worse if do not start to reduce the frequency of watering and feeding because we would send the wrong signals to our house plants by encouraging further new growth. All these factors mentioned above contribute to poor plant care and are known causes for death in house plants during the winter months.
To further increase confusion, some conditions which are appropriate for one group of plants may be intolerable to others present in that very same room. It is also unrealistic to switch the heating off in our homes just to recreate a more wintery temperature.
If we wanted to do the best for our house plants, we should start at the beginning: right when we purchase them. Immediately, we must check the environmental requirements of the different species and varieties, and we should compare these with the conditions that we can realistically provide in our own homes. For example, take a citrus tree which thrives on patios through the summer months. By reading the label, we know that this plant will require a constant 10°C temperature and access to direct sunlight even in winters. If we cannot provide the plant with these conditions – as often the case of British patios, which are known to reach freezing temperatures – they will die off in the winter.
The average home lacks light in winter months, but due to the central heating the air is rather dry, which not too many house plants can tolerate. The Dracena trifasciata, Dracena marginate, Aglaonema sp. and Bromelia are fine with these conditions when water is poured into their funnel shaped leaves.
Cactuses and sedums can also tolerate the dry and hot air but struggle in poor light conditions. In these conditions they would produce scruffy and weak new growth, so we are better off over wintering them in cellars, garages and darker rooms, where the temperature does not exceed 5-10°C and light is scarce, thus forcing them into a dormant status.
Generally, the variegated varieties and flowering house plants can also suffer from lack of light (for example Sinningia cardinalis, Sinningia speciosa, Monstera deliciosa, ficuses, cyclamens, African violet, azaleas, Calceolaria sp.). The best way to over winter these types of plants is to find and place them in the coolest but sunniest spot in our home, which are normally the window seals, where the temperature does not exceed 15-17°.
Orchids love the humidity, so we can even keep them in our bathroom as long as it is not pitch dark when the room is not in use. But any humid air loving plants – like ferns and orchids – can be grown in kitchens or bathrooms.
With tropical plants, we may need to insulate their pots using bubble wrap and provide an in situ humid microclimate while also finding and placing them in sunny spots in our homes. The easiest way to achieve an acceptable humid microclimate for these plants is by placing their pots on trays filled and levelled with shingle and gently topped with water. It might sound funny, but even drying our washing regularly in the same room can create enough humidity for these humid loving plants…but this could unfortunately cause mould on the walls too.
During winter months the leaves can be covered by dust, which would reduce the physiological functions of our house plants, so every now and again it is advisable to gently wipe or spray every leaf. Always try to use boiled but cooled down water to avoid unsightly spots on the leaves caused by the mineral content of the hard water. Hence, the same reason fir why it’s not advisable to shower our house plants directly.
For watering, never use cold water and always try to water with room temperature water with reduced frequency. Try to avoid having any excessive water in the saucers underneath the pots as this can lead to root rot.
We should also stop feeding the plants with water soluble fertilisers until spring. The only exceptions are the winter flowering varieties like Christmas cactus, which we can feed maximum once in a fortnight.
Ventilating the rooms is also very important, but we need to be careful as some of our house plants are sensitive to cold drifts, which can cause leaf loss. So, if we want to open the doors or windows to air the room, we might need to move the drift sensitive plants temporarily out of the way to somewhere more sheltered.
In the festive season when we need to reposition our plants because of the Christmas tree, we need to make sure they do not end up too cold, too hot, or in too dark places.
If we wisely consider the winter and summer conditions of our home when selecting new house plants and match their environmental requirements, we should be successful with growing them and would not need to worry if they survive the winter alright.