How to Protect Indoor Plants from the Damaging Effects of Winter

After living in northeast Florida for over two decades, I’ve come to realize that this region experiences only two seasons—winter and a very long summer. One thing I deeply miss from my Maine days is fall. There is nothing like feeling the crisp air on your skin, inhaling the aroma of dried leaves, and seeing entire mountaintops covered in red, orange, and yellow foliage. This change in outdoor scenery shows the impact cold weather has on plant life. However, most people wouldn’t suspect that the same exterior cold weather can also affect our interior environments. While the effects on indoor plants are normally subtle at first, neglecting to adapt our service tactics can lead to significant issues.

Managing Moisture

During the colder months, our heating systems are running day and night, which can dry out indoor plants, much like direct sunlight does. When the air around a plant becomes extremely dry, the plant responds by increasing its transpiration rate—a process of releasing moisture. Transpiration aids in maintaining plants’ health and improves indoor air quality, but a side effect of increased transpiration is yellowing leaves, particularly in plant varieties like pothos and dracaenas. This is most noticeable in older, larger leaves that begin to pale. If not addressed by the next service date, the leaf will likely be completely yellow, signaling a problem to everyone passing. As interiorscapers, we understand that foliage is reacting to climate change, but the average person may mistake this as neglect. By recognizing and addressing these early signs of leaf stress, we can prevent further damage and dispel any notions of poor plant care.

To combat dry air caused by heating systems, place a humidifier near plants or consider placing plants in groups, which creates a more moisture-rich environment.

Avoiding Danger Zones

Most indoor plant varieties are from tropical regions where temperatures are stable and range from 75 to 85 degrees. While no plant will be particularly happy when placed under a vent or near a drafty door, certain tropical foliage—Natal Mahogany, aralias, and orchids, to name a few—simply will not survive in these areas. These plants will deteriorate quickly if exposed to direct airflow or fluctuating temperatures in a drafty location. When servicing a building, it’s important to identify and avoid these “problem areas.” If possible, reposition plants to locations where they are out of the direct blast of vent heat, drafty windows, or high-traffic doors.

Preventing Pest Outbreaks

Winter is a prime time for spider mite infestations. During one of my first winters in the business, I placed a beautiful majesty palm in a second-floor conference room. Within a month, I found the top covered in fine webs. After wiping the webs away with a wet rag, I knew spider mites were the culprit. Soon, palms on various floors of the building were showing signs of infestation. I learned from this experience that spider mites can easily travel through ventilation systems, especially in dry conditions. Because the indoors lack natural outdoor deterrents like wind and rain, spider mites can overrun an entire building quickly.

To combat spider mites during winter, I mist plants every service day, which helps keep the spider mite population down. Regular inspection is key. I examine both the top and bottom surfaces of the leaves for any signs of infestation—tiny black dots, pale green or spotted leaf color (indicative of chlorophyll loss), and fine webbing. Once a plant is infected with spider mites, you are in for a long, challenging battle. These pests rapidly reproduce and have a strong resistance to chemicals. Therefore, it’s always best to take preventive measures from the beginning. Being thorough and proactive in checking for any signs of spider mites, especially on plants with delicate, paper-like foliage like palm fronds, cordylines, ivy, and marginatas is essential. At the first sign of an infestation, quick action can save you from a winter of misery and the high costs of plant replacement.

Caring for Indoor Plants Through the Seasons

Remember that indoor plants are more than just decorative pieces—they’re living beings reacting to their environment, much like us. So, as you navigate through the seasons, from the chilly winter to the warmth of summer, don’t forget the needs of your indoor plants. With a bit of attention, you can ensure your indoor plants continue to thrive, no matter the weather outside.