St. Paul, Minn. (December 11, 2003)—While houseplants don't get the flu as we know it, the winter months can make them more susceptible to a variety of diseases. To keep indoor plants healthy, the following are some tips offered by plant doctors from the American Phytopathological Society.Inspect a plant before you buy it. Don't buy plants with leaves that are dried and brittle, have spots, or are yellowing or wilting. Look carefully for mites, mealybugs, scales, and aphids, which can resemble plant parts. These pests often hide underneath leaves or on the leaf stems and may move when disturbed.
Although plants have been grown in homes for thousands of years, it hasn't been without a few problems, states A. R. Chase, professor emeritus, Mid-Florida Research and Education Center, University of Florida. "Plants didn't evolve in our homes which means they don't naturally adapt to the environmental conditions that occur there, especially during the winter heating season," she said.
But, Chase states, there are a few simple things that you can do to keep your houseplants healthy during the winter months.
Put a new plant in a separate room away from other plants for a while. This helps to prevent infecting your other plants with anything brought in on your new plant. If the plant still looks healthy after three or four weeks in its new home, you can move it.
Be sure your plant pot has good drainage. Excess water drowns roots and encourages root rot.
Make sure your plant gets what it needs. Not all houseplants are alike and many vary considerably with regard to moisture, temperature, and fertilization needs.
Clean the foliage. Dust and dirt can interfere with a plant's natural processes. Every few weeks, clean your plants by wiping the leaves with a damp cloth or by putting them in the shower or sink and rinsing with lukewarm water.
Avoid temperature extremes. Placing plants near large windows, radiators, or furnace vents often creates more extreme temperatures than people realize and plants can tolerate.
Be careful about moving plants. For example, do not place a plant in a sunny south window if it has been grown in a less bright location, otherwise a white to brown burning of the leaves may occur.
Don't mist your plants; it promotes disease. Use a humidifier or place pots on a bed of wet gravel if more humidity is needed.
The American Phytopathological Society (APS) is a nonprofit, professional scientific organization dedicated to the study and control of plant diseases, with 5,000 members worldwide.