By Harvey D. Goodman
The shorter days, cool temperatures and bare trees divert our attention from outside gardening tasks to those closer to home – and 1 do mean literally closer to home ; that is your house plants.
In this week's column, I want to discuss a concern that often becomes out of control and can lead to an early demise of your houseplants… not to say a sense of discomfort for the human inhabitants of your home. The topic is “insects. ”
Houseplants are particularly sensitive to infestation by a variety of insects. Most of the time, the insects are endemic to the nursery where the plants are grown, and are easily transmitted to other plants. Plants in a greenhouse or nursery are grown quite close together, so in a relatively short time, the infestation could affect the entire stock of plants.
The most cormnon pests are : Scale insects, Aphids, Greenhouse Whiteflies, and Mealy bugs. They all have in common an insatiable appetite that is fulfilled by munching away at the plants' leaves at one time in their life cycle, or simply ingesting the sap.
Honeydew, an excretion from these insects resulting from an excess of ingested sugary sap, makes the plant appear very sticky, and often can be found marring the finish on furniture below the plants.
A quick primer on each insects' appearance, will allow you to quickly recognize the culprit. Mealybugs are white, cottony insects that often appear on the underside of leaves or stems and at points on the stem where leaves are attached. The insects tend to congregate, thus giving a cottony appearance.
Greenhouse Whiteflies are tiny winged insects that feed on the underside of leaves. When the leaves are touched, the insects flutter around the plant, but quickly return to their dining area. The larvae, sometimes no larger than a pinhead, cause more damage than the adults as larvae are constantly feeding.
Aphids are tiny non-winged insects that tend to congregate or cluster on buds, young stems and leaves. As with their cousin pests, these insects suck the plant's sap and excrete excess food material as a sticky honeydew.
Scaly insects give the appearance of brown crusty bumps. These insects have a rather interesting life cycle. After hatching from eggs, the larvae, sometimes called crawlers, move about the plant or spread to other plants growing nearby.
The soft-bodied crawlers eventually insert their mouth parts into the vascular tissue of the plants, and starts to draw in the sap. At this point, the crawlers legs' atrophy, and a hard covering develops around the insect. The insect will now remain in that area for the rest of its life.
Controlling these insects is easier said than done. In many instances, once the infestation is found, it often has spread to other plants, and may have resulted in total infestation and damage to the original host plant. Where they are observed, immediately attempt to remove them using a Q-tip dipped in alcohol. Wash the plants with soap and water and attempt to remove all insects that are visible.
Several insecticides are available on the market that can be used to kill any remaining insects, and to prevent a reccurrence. A product called Orthene or Resmethrin is both a contact and systemic insecticide that will kill the insects.
This product is toxic, and I advise that it should not be used in a home where young children or pets may handle the plants. Safer is the brand name for a relatively non-toxic insecticidal soap that can penetrate the exoskeleton of these insects and place them in insect heaven.
Always remove and discard heavily infested leaves and branches and isolate the infected plant until you are confident that the infestation has been controlled.
Inspect new plants thoroughly before putting them in the house and be on a constant vigil for new infestation. The sooner you spot the insects, the easier and more successful you will be in stopping their menacing feeding habit that destroys your houseplants.
Plant Tip
Ovenvintering OVERWINTERING? geraniums is relatively easy and done properly will free you from purchasing new plants next year. Dig out the plants and shake off most of the soil. Put the plants in a paper bag and put another paper bag over the first. Keep them in an area that is cool but not too moist.
The following spring, shake off any remaining dirt. Cut off the top of the plants back to stubs, and cut back some of the roots so that the plant can fit into a 4-or 6-inch pot.
