House Plants & Insect Pests

Small green aphids eat roses and other plants.

Despite being removed from the outdoors and all of its bugs, house plants still can attract insect pests. Pests can damage house plants in a variety of ways, including spreading fungus and eating plant foliage. Prevention, pest identification and treatment can help get rid of house plant insect pests.

Types

Some common types of houseplant insect pests include mites, aphids, mealybugs and whiteflies.

Aphids are small green bugs, whiteflies have small white wings, mites look like tiny reddish spiders, and mealybugs are white and look like cotton. Larger pests, such as caterpillars and beetles, are less common indoors but may still show up on houseplants

Effects

Different types of insect pests harm plants in different ways. Aphids tend to eat plants and spread mold problems. Mites, mealybugs and whiteflies all cause plants to turn yellow as the bugs suck their juices out. Larger insect pests, like caterpillars, eat house plant leaves and destroy the plant foliage.

Prevention

Prevent house plant pests by carefully choosing house plants from reputable gardening stores and nurseries. Avoid buying plants with yellowing leaves, which could be a sign of difficult-to-see mites. Keep new house plants away from existing house plants for a while so any hidden pests do not spread, as recommended by the University of Minnesota Extension. Repot new plants into sterile pots and sterile potting soil, because pests from old soil and pots can survive in storage and spread to new plants.

Natural Removal

Pick off large insects by hand. Colorado State University and the University of Minnesota also recommend washing away aphids and mites with water. Do not let plants dry out too much or sit in too much water, because both overly dry and overly wet conditions leave plants susceptible to different pests.

Control With Predators

Common plant pests have natural predators that do not damage plants. The National Gardening Association recommends introducing ladybugs to get rid of aphids and the eggs of other insect pests. Predator mites can eat other types of mites that damage plants. Whitefly parasites and mealybug parasites harm their host insects, and gardeners can order them through the mail.

Chemical Solutions

Insecticidal soaps and sprays can help kill house plant pests. Since insecticides often contain harsh chemicals, gardeners should not spray them in areas where pets or children may come in contact with the plants or in areas with poor ventilation. Many gardening stores also sell horticultural oils, which smother mites, scales, aphids and whiteflies.

References

• Colorado State University Extension: Managing Houseplant Pests
• Indoor Potted Plant Pests
• University of Nebraska - Lincoln Extension in Lancaster County: Houseplant Pests
• University of Minnesota Extension: Houseplant Insect Control
• National Gardening Association: Ladybugs