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Kill parasites on plants with soapy water, pesticide sprays

Spider mites, mealybugs and hard-shell scales are pests that attack houseplants, but, if detected early, they can be controlled with little effort. Unfortunately, they may not be noticed until they have caused serious injury to your plants. Spider mites are tiny creatures that love many types of indoor plants. They are especially fond of palm, schefflera, spider plant, ivy and weeping fig. The first indication of the presence of mites is dusty-looking leaves. Upon closer examination, you'll find a fine webbing on the bottom of the leaves. Mites feed by sucking out plant fluids. Leaves on the infected plant become speckled and yellow, and eventually drop off. Mites can be controlled with a soapy spray. Mix your own by adding 1 teaspoon of liquid dishwashing detergent to water in a 32-ounce plastic spray bottle. Be sure to spray the underside of leaves as well as the top, and apply a second spray seven days after the first. The second application kills mites that hatched from eggs after the initial application. Mealybugs are oval-shaped insects about 1/4- to 2/3-inch long. They are covered with white powder and have white "spiky" projections coming from their bodies. They usually are found at the base of the leaves or on the stems. Mealybugs crawl, but usually stay fixed in one spot. They are commonly found on African violet, begonia, schefflera, jade plant, dieffenbachia and peperomia. When newly hatched, mealybugs are small and hard to detect. If you see white specks that look like cotton, these are the young mealys. Like mites, mealybugs are sucking insects and they cause leaves to drop off plants. One of the best controls for mealybugs is a safe product called Neem, which contains a naturally occurring compound extracted from the neem tree. The Neem product kills mealybugs on contact. A closely related product, also derived from the neem tree, called Neemix, also will control mealybugs. Both sprays can be found at most garden and home supply stores. Because sprays can damage African violet leaves, most violet growers treat mealybugs with a systemic insecticide placed in the soil. Hard-shell scales on plants are not as common as mites or mealybugs, but I am seeing more and more plants with them. They are typically flat and round, some barely visible, others as large as 2/3-inch across. Scales look like scabs, mostly brown in color. The sucking insect can be found under its protective scale covering. Although scales can be on any part of the leaves or stems, they most commonly are found attached to the leaf veins on the undersides of leaves. There are two effective ways to control scales. One is to treat the plant with an oil spray formulated to control scale. The two garden oils I recommend are Sun Spray and Saf-T-Side. Both are refined oils, and safe to spray on most plants. The oil coats the scales and kills them by suffocation. Test the oil by spraying a few leaves and waiting three or four days to see if there are any adverse reactions. Alternatively, a systemic insect killer such as Isotox may be applied to the soil. Isotox travels through the plant's roots up into the leaves and then is ingested by the feeding scales. Springtails - common pests found in the soil of indoor plants - are wingless insects about 1/16- to 1/8-inch long. The name comes from their ability to catapult themselves through the air 3 or 4 inches by a mechanism in their tails. Springtails can be seen flitting about in disturbed soil. Although they most commonly feed on decaying organic matter - moist peat - they also can feed on plant roots. Safer's Insecticidal Soap is registered for control of springtails in and around the home. Follow label directions as to the amount to use and the method of application. You also may want to consider repotting plants in new potting soil. The old soil should be washed from the roots of the plant and discarded, to dispose of springtails and prevent their transfer to the new soil. If a pot is overrun with large numbers of springtails, it's best to get rid of the plant, soil and all, and wash the pot.