January 16, 2004 at 11:07 a.m.
Growing houseplants continues to gain popularity. Almost every home has plants indoors, as well as public places such as airports, restaurants, shopping malls, offices, etc. Plants add life and beauty to interior environments. They increase people’s comfort level indoors and help remove potentially harmful gases from the air.
Unfortunately, they are often troubled by insects and related pests. These problems are usually manageable, often by non-chemical means, if you are alert to signs of trouble and take steps to control the pest in a timely fashion.
Prevention is the first level of defense. Check houseplants before you buy them. Isolate them from your other plants for 2-3 weeks to allow undetected problems to become obvious. It’s also a good idea to check plants very carefully each fall, regardless of whether you take them outside for the summer. Some insects and mites may have made their way indoors through window or door screens.
Choose plants that will thrive in the amount of light you can provide. A plant that is stressed from inadequate light is a more likely candidate for insect problems than one that is growing vigorously, or at least steadily. Wash smooth-leaved houseplants regularly to prevent a build-up of dust and grime. Dust filters light before it reaches the leaf surface and can also attract and harbor insects and spider mites. It also looks bad.
Clean large leaves and stems with a moist, soft cloth. If a plant has many tiny leaves, spray them with barely lukewarm water or wrap foil over the soil and tip the plant upside down and swish the foliage through a tub of water to which has been added a few drops of mild liquid dishwashing detergent.
Never use a feather duster to clean your houseplants. It’s too easy to unknowingly transfer insects or their eggs from one plant to another.
Always use sterilized potting soil, as garden soil may harbor insect pests and disease. Potting soil must also drain readily. When roots sit in waterlogged soil, they are likely to begin rotting and serve as a food source for soil scavengers that live off decaying organic matter.
Check houseplants for evidence of insects whenever you water them. You will stand a better chance of controlling these pests before they become numerous.
Inspect both tops and undersides of leaves particularly any that appear speckled, mottled or misshapen. This may be evidence of a pet problem, though there are other causes for discoloration. A ten-power hand magnifying lens will prove helpful when looking for tiny pests, eggs and cast skins.
Watch for honeydew, a shiny, sticky substance produced by aphids and scale insects. You will find it on the upper surface of leaves, as well as on table tops and other items under the plant.
Next week I plan on writing on identifying and controlling some of the pests that may have made their way into our houseplants.
Reminder: The new number for your gardening questions is 651-237-3080. The new email address is: [email protected]
Brochures are available for Bonanza 2004 “Garden Fever” which will be held at Maranatha Church in Forest Lake on March 6. Pre-registration is strongly encouraged. Call or email if you would like to receive a brochure or are interested in being a vendor.