Insect Control: Houseplants

Aphid

Aphid
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Aphids are tiny sucking insects from family Aphididae. Adult aphids are pear-shaped, measuring less than 1/8" in length. The most common aphids on houseplants are the light green ones (pear aphids), but aphids can also be found colored pink, white, gray and black. Additionally, winged aphids can appear when colonies are established and fly to infect new plants. Juvenile aphids (nymphs) look like smaller versions of the adults.

Aphid infestations tend to develop quickly, and the insects are highly mobile: they rapidly travel from one plant to another and can spread through flying or crawling.
Aphids cause damage by sucking sap from new growth. They tend to cluster at the growth end of plants and attach to soft, green stems. As a result, the new foliage may look crinkled or stunted, and the aphids are usually plainly visible around the stem. If the infestation is bad enough, the plant will begin to drop leaves. Finally, like mealy bugs, aphids secrete honeydew that encourages the growth of sooty mold and fungus.
Indoors, there is no winter to slow their reproduction, and females can continue to produce nymphs all year without pause. Thus, the aphid population can quickly get out of control.
Like most pests, the best control for aphids is defensive. Healthy, vigorous plants are less susceptible to infestation than weak, underpotted, and stressed plants. As a general rule, make sure your plants are healthy, and you're less likely to attract these annoying critters in the first place.