Indoor plants are widely used in homes and commercial buildings. They help keep us in touch with nature and, in a sense, bring the outside indoors.
With the cold-weather months upon us now, houseplants that have been outside need to be brought into the house. Most houseplants are tropical plants, and cannot tolerate our winter temperatures. Few houseplants can stand temperatures below 40 F.
Over-wintering them in the house presents a challenge because of lower temperatures and humidity and light levels inside.
Fertilization should be reduced by one-half during the winter because the cooler temperatures slow the growth down and less fertilizer is needed.
The plants should be placed where they will receive plenty of light. South- and west-facing windows are the best. The use of artificial plant lights is fine, but they usually do not provide the necessary amounts of light by themselves. Use the grow lights only to supplement sunlight, and place them as close to plants as possible to get the most benefit.
Humidity is lower inside, and the conditions can get quite dry with indoor heating. The plants should be constantly monitored for water. When watering is required, apply the water until it trickles out of the bottom of the pot. Occasionally, use a spray bottle to mist the plants to keep them moist.
Group the plants together in the same area, and place a shallow pan of water nearby to help increase the humidity.
You could also try placing the plants in a shallow tray filled with gravel and some water. Be sure to never allow the water level touch the bottom of the pot, and don't use water that is too hot or too cold. The temperature of the water should be between 62 and 72 F.
Next spring, examine the plants to see if they need to be repotted. Prune off the dead parts and the excessive growth, water thoroughly and place them outside after all danger of frost has passed.
Different plants have differing requirements. Some plants, especially succulent plants like aloes, can do with significantly less water than even African violets. Ferns do well with lower light levels, but wax begonias need much higher levels.
Knowing the cultural requirements for specific houseplants in your home will help in keeping them attractive and healthy during the cold weather months.
Timothy Daly is an agricultural and natural resource agent with the Gwinnett County Extension Service. He can be reached at 678-377-4010 or firstname.lastname@example.org.