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White Bugs on Outdoor Plants

By Lisa Larsen ; Updated September 21, 2017
Check plants for harmful bugs.
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The discovery of white bugs on your outdoor plants is certainly reason to be alarmed. Several types of white insects thrive on the leaves of healthy plants, both indoors and outdoors. Aphids, scale, whiteflies and mealy bugs are all very tiny, white bugs that are usually undetected until they have caused the host plant to show drastic signs of deterioration. These bugs will destroy your plants if left untreated.


Cottony scale is easily spotted.
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Identifying white bugs on your plants isn’t difficult. They usually gather on the underside of the leaf in large masses. Sometimes there will be a white cottony substance which appears to be a bug. The leaves often will be covered with black sooty mold. This is due to a sticky secretion from the bugs called honeydew.


Aphids may be green.
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Aphids are tiny pear-shaped insects that attach themselves to the underside of the plant leaves. There they suck the sap out of the leaf. Aphids are often white but may also be yellow or green.

Cottony Scale

Insects may be camouflaged.
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Scale appears to be a white, cottony bug on the leaf’s surface. It is actually the scale’s egg sac that is the white substance. Scale extracts sap from the leaf of the plant, causing it to wilt and die.

Mealy Bugs

Mealy bugs are a type of scale.
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Mealy bugs are part of the scale family, and are covered with a white powdery substance. They, too dine on the sap of the leaf, and leave behind the sticky substance called honeydew.


Whiteflies are winged.
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Whiteflies are most active in the warm parts of the day. They congregate on the underside of the leaf, and suck the sap from the leaves. They resemble tiny moths and are winged.


Use a cloth to wipe off mold.
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All these bugs can be treated in an environmentally safe manner. Mix dish detergent in water and pour the mixture into a mister bottle. Spray the infested plants vigorously. Repeat this process every five days until the bugs have disappeared. In instances where the sooty mold covers the leaves, use a damp cloth and gently wipe the mold away.


About the Author


Lisa Larsen has been a professional writer for over 18 years. She has written radio advertisement copy, research papers, SEO articles, magazine articles for "BIKE," "USA Today" and "Dirt Rag," newspaper articles for "Florida Today" and short stories published in "Glimmer Train" and "Lullwater Review," among others. She has a master's degree in education and is a member of the National Society of Collegiate Scholars.