Gardening: Watering houseplants can be tricky in winter
About this time every winter, my hands start getting cracked and dry. It’s hard to keep enough hand cream on them to make them look and feel good. There are times when the only thing that works is good, old-fashioned Bag Balm, a lanolin-rich salve that was originally used by dairymen on cow udders.
Houseplants go through something similar. During the winter, our furnaces kick out a lot of dry air and after a few months of this drying environment, our houseplants have an equivalent plant response; dry, droopy leaves and a dull color.
Applying Bag Balm isn’t going to help the plants, but giving them some care will help them through the rest of the winter months. First check that plants aren’t too close to furnace vents, fireplaces or are sitting on the top of the television. This is the equivalent of leaving the plants outside in hot, windy August weather. Move them to a cool space with bright indirect light. If natural light isn’t available, set them under some 4-foot long fluorescent shop fixtures set on a timer for 14 to 16 hours a day.
Watering houseplants during the winter can be tricky. Most plants go semi-dormant when the daylight levels drop in the winter and as a result, use less moisture. Many gardeners don’t recognize this and tend to overwater them out of habit. Ironically, the symptoms for a dry plant are very similar to those of one that has been overwatered: limp, yellowing leaves. To check how dry the soil is, insert your index finger to the first joint into the soil. If dry to that level, apply enough water to just run out of the bottom of the pot. Remove any standing water in the plant’s saucer so the roots don’t sit in water. This may mean only watering them every two to three weeks during the winter. Succulents may need water about once a month.
To counteract the drying effect of dry furnace air, humidity can be added to the plants’ environment in several ways. Small plants can be moved to a kitchen or bathroom that gets good light. Being close to the sink will raise the humidity for them. Keep a squirt bottle of water handy and mist plants every day. Large pans like cookie sheets or old cake pans can be filled with gravel and water and then the plants set in them. The gravel keeps the plant pots out of the water and the water evaporates and raises the humidity around them. You can add a temporary greenhouse over this grouping of plants by laying a lightweight clear painter’s tarp or clear plastic sheeting over the plants to hold in the humidity. Insert thin bamboo stakes into the pots to hold the plastic up.
Don’t fertilize houseplants until the end of March when they begin to come out of their winter dormancy. They can’t use it any earlier. As the days lengthen, increase your watering and remove any temporary greenhouses.