Care for House Plant Pests

   House plants are less susceptible to disease and infestations than are plants in a greenhouse or garden. Taking simple precautions can reduce the chances of infestation. If you buy healthy plants from a reputable source, you shouldn't have any disease problem. Crown or root rot may occur, but it is likely to be caused by poor drainage and overwatering. Loss of leaves and spotting may be caused by low humidity.

   The same basic principles of gardening apply to plants in the house as to those in the garden. It is easier to take precautionary measures, a little time spent keeping plants clean will be a good long term investment.

1..Always use clean pots and sterilized soil to prevent problems with soil pests.

2..Examine new plants and cut flowers that you are bringing into the house for the first time to be certain they are free of pests.

3..Isolate new potted plants for a month and inspect frequently for signs of disease or insects.

4..Wash leaves of plants with lukewarm water to which a small amount of mild detergent has been added. The removal of dust will improve the appearance of the plants.

5..Remove any dead leaves and inspect plants often for signs of poor health.

6..If insects are found, take actions immediately. One infested plant can be handpicked, washed and isolated. If infestation is on a large scale, take action quickly.

It is best to use insecticides outdoors if possible. The pushbutton spray cans are convenient and save the trouble of mixing sprays. Read the directions on labels carefully and follow them exactly and be certain the spray is safe for plants. When the spray is not in use, keep it covered tightly and out of the reach of children.

Pests and Control

Ants...Black, brown or red. They live in nests or colonies and are attracted to plants by certain aphids, mealybugs, and scale insects which excrete honeydew...Ants can carry away seeds or seedlings and may injure roots.

To control; soak infested soil, pots and boxes with malathion or diazinon.

Aphids...Sucking insects with soft, round or pear-shaped bodies, many colors and kinds. They usually cluster on new growth and buds. Aphids suck plant juices, causing poor growth, stunted plants, or curled, distorted leaves. They secrete a sticky liquid called honeydew, which provides a base for the growth of sooty mold.

To control; Dip or spray plants, using malathion, diazinon, or a systemic insecticide.

Mealybugs...Soft-bodied sucking insect that appear as if they had been dusted with powder. Visible to the eye, they cluster in leaf axils or branch crotches. They secrete honeydew on which black mold grows. Sucking of mealybugs stunts or kills plants.

To control; If only one plant is infected, isolate it and handpick or touch with cotton swab dipped in alcohol. Otherwise dip or spray plants with malathion, being certain to wet mealybugs throughly.

Mites, Cyclamen...Too small to be visible, but when magnified are seen to be oval, semi-tranparent. They attack tender young leaves and buds. Leaves become twisted and buds are deformed. Blackening of infested parts is common. The mites crawl from plant to plant where leaves touch and can be transferred on hands or clothing.

To control; Isolate plant immediately. Dip or spray using a systemic insecticide as directed on the label. Trim off infested parts of plant where practicable.

Mites, Spider...Cannot be seen unless there are many together. Flat, oval, usually red. Found on the underside of leaves. Leaves may yellow and die, or drop off. Infected plants become stunted and may die.

 To control; Spray or dip plants using a systemic insecticide or diazinon. Be certain to wet the underside of the foliage.

Scales...Many kinds. Some have a shell-like covering or scale that covers the entire body. Browns and grays are predominant colors. Some kinds attack leaves, others stems, some both. Scales are sucking insects that use plant juices for food. The result is a stunted plant or one that grows poorly. Scales also secrete honeydew which attracts ants.

 To control; Spray or dip, using malathion. Repeat as directed on label. If only one or two plants are infested, washing is an effective control method.

Thrips...Very small, barely visible. They are slender and colored tan, brown, brownish black or black with lighter markings. Young are whitish to yellow or orange. Some species carry droplets of black excrement on their backs, adults fly or leap when the plant is disturbed. Thrips cause injury on plants or flowers by rasping the plant tissues and obtaining the juices. This rasping damage is visible, which appears as distortion of leaves and flowers.

To control; Dip or spray plants using malathion, diazinon, or a systemic insecticide.

Whiteflies...Very small, common pests with white, wedge-shaped wings. They flutter about when the plant is disturbed, resembling small snowflakes. Young attach to under surfaces of the leaves. Whiteflies feed on plant juices, turning leaves pale. Surface of the leaves become covered with excreted honeydew, and sooty mold may develop.

To control; Dip or spray plants using diazinon or malathion. Several applications may be needed-follow label directions carefully.