Indoor plant care is always tricky. While it's all fine and dandy to take care of them when the summer sun is shining, keeping your plants alive in winter can feel like a whole ’nother story. Being a houseplant enthusiast is akin to having several silent children, all with finicky needs and limited ways of communicating them. If your green thumb is feeling a little yellow or brown these days, fear not! I interviewed several experts to figure out exactly how to keep your plants happy during the colder months. Here’s what they had to say.
First Things First: Manage Your Expectations
The fact of the matter is, most plants don't look “happy” during winter. Because it's winter. Unless you have a fancy automated hydroponic garden at your disposal, your greatest tools will be patience and attentiveness. Most plants have new growth during the longer days of spring and summer and enter a period of slowness or dormancy during shorter days of autumn and winter.
Brian Wheat, professor of horticulture at Trident Technical College, says, “Stop trying so hard and worrying so much” and reminds us that time and patience are crucial (and that maybe we shouldn't anthropomorphize plants). “Perhaps we forget the fact that what may look like a struggling plant today could be thriving in, let's say, three to four weeks, if we give it a chance.” He adds, “Nine times out of 10, your plants are OK and don't really need much from you. In fact, you might be doing them more bad than good by being a hummingbird plant parent (I just made that up, it's kind of like helicopter parenting, but for plants).”
Tatiana Anderson, cofounder of Top Tropicals, says not to panic if growth slows or a few leaves drop. “What you want to see is steady color, firm leaves, and no major changes," she says. "A ‘happy’ winter plant often looks calm, not busy.”
Water
Watering is the bane of my existence, as evinced by the monstera that I accidentally drown every other month.
“One of the biggest issues with house plants is overwatering, which can lead to problems like root rot," says Wheat. "This is especially challenging during the winter months,” And it can be even trickier if your plants are outside during the warmer months. Moving them indoors means moving them to an environment that's drier and cooler.
“Relative humidity is usually between 30 and 50 percent inside, whereas plants generally prefer a higher humidity,” Wheat says. He points out that the soil or media will dry out faster, especially in heated homes. But that doesn't mean you need to water plants more in winter. Because they aren't growing as actively, they're doing less “plant stuff” such as transpiration and photosynthesis. That means they're using less water.
Justin Hancock, Costa Farms horticulturist, says to be wary if you usually water your plants on a schedule. “If you’re used to giving them a fixed amount of water every week, you could inadvertently overwater in winter if they don’t drink that much. If you’re in doubt, it’s almost always better to let houseplants get a little too dry than to keep them consistently too wet.”
And, according to Andrew Connolly, founder of Little Flower Cottage, you should “try to always use room temperature water, as really cold water can shock the plant.” He adds that “overwatering is the fastest way to lose a plant in the winter.”
Anup Mutalik, chief editor at Houseplants Nook, says, “We always do the finger test and water only when the top 2 inches are dry. Overwatering is a bigger risk in winter, because evaporation slows down. For most plants, we cut back to watering once every 15 days!”
Wheat advises to make sure your plants aren't bone-dry or soaking wet. “Get to know the weight of your pot when it is dry and watered,” he says. “Feel it out." Anderson adds that if the soil on top is dry and the pot feels light, it's time for water. Per Wheat: “If your plant is wilting and the soil is dry, it needs water. If your plant is wilting and the soil is wet, it's overwatered.” He also reminds us to be patient. “A simple change you make can take days or weeks to show an impact.”
Light
Move your plants close to windows so they can get enough light. “Most plants prefer direct to indirect sunlight. An east-, or southeast- to southwest-facing window can provide this. North-facing windows do not. If you don’t have any windows providing sunlight, artificial light will no doubt be a requirement,” says Wheat.
Hancock adds, “Put a thermometer at the windowsill and check it periodically (particularly at night) first. Make sure the windowsill doesn’t drop below about 55 [degrees Fahrenheit] or so; cooler temperatures than that can stress some species.” Connelly recommends rotating plants every week or so, too. “Basically all sides need to get roughly the same amount of light.”
Every expert I spoke with recommended snagging a few inexpensive full-spectrum grow lights to supplement your plants during the winter. (I'm working on a buying guide on the Best Grow Lights, so look for WIRED-tested recommendations soon! WIRED editor Kat Merck likes the full-spectrum bulbs above, which she puts in can lights for extra-tall plants in dark corners.) Mutalik says, “You can just buy a couple grow lamps and keep rotating plants in and out of them so you don't invest too much at once.”
Experts also recommend ensuring that your plants' leaves are free of dust, which blocks the light. Hancock points out that dust can accumulate faster in the winter due to drier air and the use of furnaces or other heat sources like fireplaces.
“Any dust film that builds up reduces the amount of light that actually reaches the leaf. So a really dusty plant in a sunny window might only be able to access half the light coming through if a dust layer is blocking the other half,” he says. You can gently wipe them with a soft, damp cloth or use a specialty tool designed for the purpose, like Goha's microfiber Leaf Sweep, above.
Humidity
Hancock says that, similarly to how humans can experience dry skin and chapped lips in the winter, plants can feel the effects of low humidity and dry air, too—especially plants with thinner leaves. “As a general rule, the thicker the leaf texture, the more resilient a plant is to low humidity,” he says. He recommends boosting humidity by “investing in a small humidifier or grouping plants together, [since] they release moisture in the air as they breathe.”
He also says that most plants are comfortable with the same humidity you are—about 40 to 60 percent. And you can skip the misting. “Misting adds humidity for only a couple of minutes. It’s not enough to actually help the plant, unfortunately,” says Hancock.
“If leaf edges turn brown or curl, that’s usually a humidity cry for help,” per Mutalik. “We keep humidity-loving plants like calatheas, ferns, and marantas grouped together on pebble trays and run a humidifier nearby.” (Our WIRED-tested favorite is above.) He says that a windowed bathroom is also great for tropical plants that love high humidity. “It doesn't have to be fancy,” adds Anderson.
Heat
We already covered that you should monitor the warmth near your windows to ensure it doesn't drop below 55 degrees Fahrenheit. But ambient air temperatures can affect your houseplants as well. “If you’re feeling chilly, your plants probably are, too,” says Hancock. “And they can’t put on a sweater.”
You'll also want to watch out for drafts. “If you have a houseplant near a heating vent where it’s getting exposed to air that’s noticeably warmer or cooler than the ambient air temperature, it can stress your plant, causing leaves to yellow prematurely,” says Hancock.
Drafts can be caused by exterior doors and windows. Connolly points out that heating vents and space heaters can be detrimental, too. Plants “like the temperature to stay consistent and not be swinging back and forth between hot and cold.”
Awareness is key when it comes to heat and airflow. “We keep anything leafy or tropical at least 2 feet away from heaters and ensure windows are well-insulated,” says Mutalik.
Pests
If you're bringing your plants indoors from outside, experts recommend quarantining them for a period of time to ensure they aren't hosting any pests that could affect your other houseplants. (Because let's be real—nobody has just one houseplant.) “Catching them early saves a lot of heartache,” says Anderson.
Mutalik and the rest of the Houseplant Nook quarantine their plants for two weeks. Check under every leaf for mites, mealybugs, or gnats. If you encounter pests, there are a few ways of addressing them that can vary based on preference and plant species. Wheat removes them manually if possible, and wipes them down with a cloth or a light vinegar solution before moving on to other, more aggressive measures like horticultural oils or soaps if needed. (Editor Kat Merck uses the insecticidal soap above on her houseplants and hydroponic gardens.)
Connolly wipes plants down with a cloth and then rinses them in the sink. And Mutalik says that Neem oil or castile soap can work wonders if you catch the pests early; wipe the leaves, especially broader leaves, every two weeks to prevent infection.
While many winter pests hitch a ride indoors, Hancock points out that dry, warm conditions (like those found in heated homes in winter) are the ideal environment for spider mites.
“Regularly washing plant leaves can help dislodge spider mites and help keep the population low. If you’re just seeing spider mites and don’t want to spray, consider investing in beneficial mites. Beneficial mites will eat the spider mites and don’t harm your plant,” he says.
Fertilizer
Fertilizer is always a little confusing, and it can be even more puzzling in the wintertime. “I would say, don't even bother to fertilize your house plant if you're using an over-the-counter potting soil. Most of these soils have slow-release fertilizer in them that is sufficient for plant growth,” says Wheat.
If you have an older plant with tired soil, or a particularly “heavy feeder,” you can opt for a slow or controlled-release fertilizer—or just repot it with fresh soil. (But be aware that winter isn't usually the best time to repot a plant, and you may want to wait until the growing season arrives.)
“Keep it gentle,” advises Anderson. “If you do feed, make it a weak solution once a month, just enough to keep the leaves green.”
Mutalik says there are just a few exceptions. “We pause all fertilizing during the winter dormancy period, unless a plant is actively growing (like some pothos or philodendrons that surprise us).” He says that feeding a dormant plant stresses it out, similarly to overwatering, and can cause leaf burn or browning edges. “If you really want to fertilize, and the leaves are actively being pushed out, dilute the fertilizer to one-fourth and add it to the base right after watering and flushing the soil.” (Editor Kat Merck uses and recommends the fertilizer above.)
Signs of Trouble
Over winter, what you want is a stable, calm plant. “If any of the leaves are turning yellow or the soil smells nasty, those are bad signs,” says Connolly. And if you do notice something going awry, it's best to make small adjustments rather than throwing the book of problem-solving at your houseplants. Gradual changes are the best way to help a plant bounce back, rather than risking stressing it further. There are even apps that claim to help you figure out what's wrong with your plants. (I'm testing a few out and will recommend one in an upcoming guide.)
I'll let Wheat take it from here. “Don’t worry. Take it easy. Stop trying so hard. Winter gives way to spring and your plants go through cycles where they make look ‘happy’ or ’sad’ but it’s all part of any plant’s natural lifecycle. Be patient—but attentive—and you’ll see your plants thrive.”
Meet the Experts
- Brian Wheat, professor of horticulture, Trident Technical College
- Tatiana Anderson, cofounder, Top Tropicals
- Justin Hancock, horticulturist, Costa Farms
- Andrew Connolly, founder, Little Flower Cottage
- Anup Mutalik, chief editor, Houseplants Nook
Power up with unlimited access to WIRED. Get best-in-class reporting and exclusive subscriber content that's too important to ignore. Subscribe Today.
