The purple passion plant is a favored houseplant because of its green leaves that have light purple fur coverings, which look and feel like velvet. The purple passion plant occasionally suffers from insect infestations. With prompt treatment, the plant will suffer few adverse effects.
The spider mite is so small it's difficult to see with the naked eye. Spider mites damage the plant by sucking its nutrients. When the purple passion plant's leaves turn bronze, it's the first sign that spider mites are present. The foliage may also display brown flecking. If you look closely at the leaves, you may be able to see fine webbing. Without prompt control, the houseplant may begin to lose its foliage. Remove all damaged leaves and promptly dispose of them. Hose the plant off in the sink or shower to remove the pests. Continue to wash away the spider mites every week until there are no signs of the pests.
Aphids congregate along the plant's stems and new growth. The pests suck the sap of the plant by piercing the plant's outer layer with their sharp mouths. A heavy infestation will cause wilting. The excrement of aphids is sticky. This is known as honeydew, which grows black mold, rendering the plant unsightly. It also reduces the leaves' photosynthetic abilities. Hose off the aphids from the purple passion plant. If the infestation is heavy, use an insecticidal soap and water. Pyrethroid insecticides also help control the pests.
A purple passion plant that is infested with mealybugs exhibits a cottony substance on its stems. The substance is produced by the female mealybug. It's used to hide her eggs. Mealybugs can infest both the foliage and roots. The plant will wilt and suffer foliage loss. The pests suck the sap and produce excessive honeydew excrement. Dip a cotton swab in alcohol and touch the adult mealybugs. Use an insecticidal soap to gain control of the infestation. Systemic insecticides that contain disulfoton and imidacloprid will kill the pests on the plant roots.
These pests suck the plant's sap and excrete honeydew excrement. While both the whitefly adults and nymphs feed on the plant's sap, the nymphs remove the greatest quantity, according to the University of Missouri. The whitefly nymphs appear as small white specks on the plant's foliage. Nymphs attach themselves to the undersides of the plant's foliage and feed for about four weeks before pupating into an adult. The plant's leaves will turn yellow and dry out. Eventually, the leaves will fall from the plant. Use an insecticide that contains sumithrin, pyrethrins, tetramethrin or resmethrin to kill the pests. Insecticidal soaps and horticultural oils eliminate the nymphs.
Scale insects affix themselves to the plant's stems and sometimes on its leaves with their powerful mouths. The insects produce a waxy substance that covers their bodies. The waxy substance looks like a white or tan scale on the plant's stems. The insects suck the sap and produce honeydew excrement. The pests causes the plant to wilt and its foliage to die. The overgrowth of black mold from the insect's honeydew excrement further weakens the plant by reducing its photosynthetic ability. Apply insecticides that contain pyrethrins and resmethrin once per week to control the scales. Insecticides that contain bifenthrin and permethrin offer longer periods of control. A systemic insecticide will also eliminate the pests.
- Missouri Botanical Garden: Gynura Aurantiaca
- Colorado State University Extension: Spider Mites
- Colorado State University Extension: Managing Houseplant Pests
- University of Missouri Extension: Managing Whiteflies on Indoor and Outdoor Plants
- Missouri Botanical Garden: Black Mildew and Sooty Mold
- North Dakota State University: Houseplants