Cool weather is upon us. Winter brings many changes to the way we treat the garden. But what about care for our houseplants over winter? You need to make changes to for both your indoor and outdoor gardens.Â
Even though most houseplants don’t lose their leaves in the winter, most of them still experience a period of dormancy. You may have noticed that your monstera—which usually produces a new leaf every two months—hasn’t pushed one out for a minute. Expect your indoor garden to slow down or stop producing new growth altogether during the cold months.
This is not something to worry about. It’s just the natural way of things. Less sunlight signals to them that it’s time to take a break and simply get some rest. It’s important to pay attention to the changes they are going though. More specifically, their soil, moisture level, and overall environment, as well as a few other factors. Let’s talk about how you can adapt your care to the needs of your houseplants in the winter.Â
Water Sparingly
Most plants won’t take in nearly as much water in winter as they did in the growing seasons. This means that if you don’t adjust your watering habits, you’re likely to end up with a serious case of root rot. Root rot occurs when the soil remains overly wet for an extended time without drying out between. The organic matter starts to decay and becomes a host for fungus.Â
Fungus is bad for dormant root systems. It causes roots to break down, preventing them from transporting moisture and nutrients to the foliage. The foliage will start to look sad, with yellow around the stems and a general lack of vigor.Â
To prevent this from happening, scale back on watering during the cooler months. You’ll be able to tell when it’s time to slow down because those pots that are usually dry by watering day will still be moist. Now is the time to make sure you check the soil before watering.Â
You’ll notice when they start to rebound in the spring in the same way. Suddenly, the soil that was staying moist will dry out much faster. This is the signal to resume your usual watering routine.
Cut Back on Fertilizer
For the same reason they need less water, your plants need less fertilizer while they are dormant. There are more than enough nutrients in your potting soil to carry them through dormancy.Â
The exception to this is orchids, which continue to grow and develop flowers during the cold months. Continue fertilizing and watering them as usual until they bloom, and then give them a rest.Â
For just about everything else, put a hold on fertilizing. You might not think this is important. After all, how can some extra nutrients hurt? The reality is they can hurt quite a lot.Â
Fertilizer that the roots can’t take in just sits there and does something unfortunate. It desiccates the roots. You’ve probably heard of fertilizer burn. Well, this is how that happens. When a plant can’t use the surrounding fertilizer, it burns the roots, drying them out and preventing them from taking in water to deliver to the foliage.Â
If your plant has fertilizer burn, you may see browning on the leaves, as though it’s sunburned. The brown, crispy ends will slowly creep inward, killing the foliage. Give them a rest for a few months from fertilizing, then resume in early spring when they start pushing out that first spring leaf.Â
Provide More Light
As the daylight hours get shorter, your plants will receive less and less light as well. This can be especially problematic for plants that need full sun exposure. Even for those who prefer indirect light, the decrease in exposure can lead to a lack of vigor as they produce less chlorophyll.Â
It’s true that, as most houseplants enter some degree of dormancy in the winter, their care, water, and nutrient needs decrease. But, their light requirements remain mostly consistent. This means that you’ll want to make adjustments to their position in relation to their light source.Â
For species that prefer indirect light, simply move them closer to the window or remove buffers. For your full-sun plants, consider a grow light to help meet their more significant needs. For plants that appreciate lower light and less day length, it’s fine to leave them where they are.
The daylight hours aren’t just shorter in the winter. The angle of the sun changes, so you may find that some windows that get plenty of sun in the summer are suddenly in the shade for much of the day. You may even need to relocate some to different windows altogether.
Keep the Temperature Steady
Many houseplants are tropical, and they need warm temperatures to thrive. Some fluctuation mimics their natural environment, but too much can be stressful. The ideal range for most is between 65-75°F (18-24°C), with a dip of no more than 10° at night.Â
While your thermostat may reflect these temperatures, plants located near windows and doors may experience colder temperatures. I’ve had more than one start to wilt and look stressed after an especially cold night. Remember that if it’s freezing right outside a window, it’s likely to be quite cold on the inside of the window as well.Â
Most tropicals can withstand some cold weather but start to suffer around 50°F (10°C). They may lose leaves if exposed to extreme shifts. Watch out for drafts, as that additional cold air can make a big difference. On very cold nights, consider moving plants away from windows.Â
Raise the Humidity
Tropical species are true moisture lovers. They are native to humid climates and need humidity to maintain healthy foliage and, in some cases, roots. Keeping them in a bathroom or kitchen with higher humidity levels may be enough for most of the year.
In the winter, and particularly when you’re running the heat in your home, the air will be drier. In some cases, much drier. If you’ve ever noticed an increased need for moisturizers for your skin in winter, you’re not alone. If your body is registering a lack of moisture, you can bet that your plants are feeling it even more.Â
It’s worthwhile for both you and your plants to pick up a humidifier or two to keep around during the winter months. Dry air is harder on your body, specifically your skin and respiratory system. A humidifier in the home in winter counteracts the effects of an air-drying heater. No more dry sinuses and throat, and no more chapped lips!
Just like us, humidity is good for most types of houseplants, particularly when you are trying to care for them during cold, dry winters. Turning one on in the home for even a few hours per day will be beneficial for that foliage.Â
Check For Pests
It’s a good idea to watch out for pets all year, but there are a couple of reasons why it’s even more important in the winter. The first factor is dormancy. Your houseplants aren’t taking in the same amount of nutrients and water as usual, and that can make them more sensitive to pest damage.Â
The second has to do with bringing plants indoors for the winter. I will tell you, from experience, that insects can come in on your outdoor plants and be difficult to get rid of. I had spider mites get in a few years ago, and I swear I still see their little webs from time to time.Â
The best way to handle this is by inspecting your outdoor plants thoroughly before bringing them in. You could use this opportunity to repot them to avoid insects traveling into the house in the soil. Treating with dormant oil can help eradicate some pests in their early stages.Â
If you’ve already brought them in, use this time to inspect and try to control any issues. If you can catch them before they spread to others, all the better.Â
Tidy Up
Winter isn’t a great time to prune. It’s better to wait for spring to do any major trimming and propagating. However, it’s a good time to clean things up so that they go into their growth phase strong. Inspect for any damaged leaves, and make sure there are no diseases to deal with.Â
Another task to take care of is actually cleaning your leaves. Indoors, leaves can collect dust. This dust interferes with photosynthesis, which is already challenging in winter. Use a soft cloth and water. You can also add a small amount of gentle dish soap to the water.Â
By trimming away damaged foliage, your plant will redirect energy away from those leaves and into producing more. Cleaning them will increase their ability to produce chlorophyll during times of less sunlight.Â
Don’t Re-Pot
Late winter is a fine time to re-pot your houseplants. But ideally, you want to hold off until just before spring, when they are about to re-enter a growth phase. For the time being, it’s best to let them spend their dormancy as they are.Â
As I mentioned, the exception to this is plants that you bring in from outdoors. It’s beneficial to re-pot those just before bringing them into the house to avoid bringing pests in with them.Â
Don’t Stress About Falling Leaves
If you notice a few of your plants dropping a leaf or two, try not to worry much. Many of them will drop their oldest set of leaves once per year, and generally in the winter. Even orchids shed their oldest leaves, usually just before they bloom.Â
This doesn’t happen because there is a problem. It’s just a way for them to conserve energy. Once they begin to grow again, they can direct their energy into producing a new set to replace the leaves they lost.Â
If you see more than one set of leaves start to go, you may have a problem. More than one set can mean an issue with root rot or a lack of water and nutrients. While they need less during the winter, they can’t live entirely without water for an extended time.