Houseplants are key to my happiness, especially during the doldrums of winter. Having a little greenery in the house (or a lot, in my case — about 40 different plants) has beneficial effects for the mind. Studies at the University of Michigan and Texas A&M have shown that studying or working around houseplants results in increased concentration and productivity, and can even increase memory retention by 20%. This comes in handy for anyone that can keep plants at their workplace, including those of us working from home this season.
But there’s a little bit of a learning curve to taking care of them when there’s less natural light, colder temps, and lower humidity indoors. Low humidity can be an especially big problem for plants in the winter. Many of our plants need humidity to fall between 30 and 50%. But indoor humidity naturally drops as low as 25% when outdoor temps are 0 degrees Fahrenheit.
That being said, caring for your houseplants in winter doesn’t have to be difficult! Here are a few tips to keeping them happy:
• Water less — as a general rule of thumb, water your plants about a quarter as often as you did during the summer. There’s less natural light, so plants slow down their growth since there’s just not enough resources available to make food from sunlight. During the month of November, we see about 10.5 hours of sunlight decrease to about 9.5 hours of sunlight per day, and on top of that, we are much more likely to see cloudy days during the winter than we are in the summer.
Note: Some plants will have requirements that differ from this generalized advice. Be sure to do a little research on your plants if you think that their needs are not being met during the winter.
• Increase humidity — plants like ferns and certain tropicals need higher humidity in the winter since our indoor air gets so dry. One way to do this is to move vulnerable plants to a room where you can run a humidifier throughout the day. Another way to accomplish this is to set your plant pots on a tray of pebbles that you keep wet. The pebbles slightly increase the humidity in the immediate area around them, providing a more favorable environment for your plants to thrive in. Finally, grouping vulnerable plants together on one table can help increase the humidity immediately surrounding them, creating a little microclimate with slightly “wetter” air than in the rest of the home.
Note: Most ferns require soil to be moist at all times (a few like to have the top layer of soil dry out between waterings). Soil will likely remain moist for longer in the winter, so you’ll still overall want to water less often.
• Set up a grow light — some plants, like succulents and cacti, need much more light than other houseplants. One way to help them out in the winter is to set up a grow light on a timer. Grow lights either contain blue and red LEDs or produce full spectrum white light. We run a timer in our home for our succulents for about 14 hours per day to help supplement natural light coming in through the windows. Many grow lights can be purchased as single bulbs that fit in a standard light socket.
Note: Cacti need watering much less often in the winter, sometimes as little as once a month. Living pebbles and snake plants are good examples of plants that will suffer if watered too often, especially in winter.
Good luck with your houseplants this winter. We hope that these tips help you and your plants as we hunker down for the winter months.
Ashley Adair is the Montgomery County Extension Educator, Ag and Natural Resource. The office is at 400 Parke Ave., Crawfordsville; 765-364-6363. She may be reached by email at holmes9@purdue.edu.
