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Managing insects on indoor plants

Quick facts

  • Choose healthy plants with growing requirements that match the indoor environment.
  • Proper plant care can minimize pest issues, reducing the need for chemicals.
  • Examine plants regularly for insects.
  • If pests are detected, isolate the plant from others.

Healthy plants have fewer pest problems

Sufficient light is important for healthy plants

Prevent, or at least minimize, pest issues on indoor plants by choosing the right plants and providing good overall care. Learn about basic care and growing needs for your plant.

Grow plants in the best possible conditions

  • Select plants with growing requirements that match the indoor environment (humidity, light, temperature).
  • Plants cannot fight off pests when they are struggling to grow in too little light, overly wet or dry soil, too hot or too cold air temperatures, etc.

Water plants properly

  • Know how much water your plant needs.
  • Water the soil at the base of the plant, not the leaves.
  • Be sure the plant's pot drains well.
    • Avoid letting plants stand in water.
    • Over-watering and poor drainage can cause root rot and encourage fungus gnats as well as other pest issues.

Understand your plant’s nutritional needs

Remove dead leaves and flowers
  • Apply fertilizer at half the recommended strength.
  • Fertilize when the plant is actively growing.

Keep plants clean

  • Keep soil surface free of dead leaves, stems and flowers.
  • Wash plant leaves with a damp cloth as dust and grime can reduce plant health.  Never use leaf shine products or milk.
  • Prune out dead branches and stems.

Use new, sterile potting soil when potting plants

  • Never pot indoor plants using soil from the garden.
  • Avoid using soil from open bags of potting soil that have sat outside for potting indoor plants. Save it for your outside pots.
  • Plant in clean pots and wash soil off of plant roots.
Check the undersides of leaves

Early detection is key to managing pests

Finding pests before they become a problem is the best way to keep insects at bay.

  • Thoroughly examine all plant parts and containers before bringing them home from the store or indoors for the winter.
    • You may need to use a magnifying lens as some pests are very small.
  • Inspect tops and undersides of leaves for insects, webbing, holes and eggs.
    • Examine discolored leaves as this may be evidence of a pest problem.
      • A ten-power hand magnifying lens is helpful when looking for pests. There are also magnifier apps for smartphones.
  • Watch for honeydew, a shiny, sticky substance made by aphids, mealybugs and scale insects found on the upper surface of leaves, and on tabletops and other items around and under the plant.
  • Check plant containers for signs of pests along edges, rims, and crevices and on the bottom of pots and saucers. Remove if found.
  • Isolate newly acquired plants for one to two weeks to allow any possible pest problems to become visible.
  • Check for pests when you water, fertilize or clean plants.
  • Use yellow or blue sticky traps to detect flying insects like whiteflies, fungus gnats, winged aphids and thrips.

How to manage insects on indoor plants

Yellow sticky cards trap flies.

Many insect problems on indoor plants can be managed using nonchemical methods, particularly if the infestation is minor.

Wash leaves

  • Wipe leaves with a damp paper towel, changing towels often to prevent spread.
  • Spray small plants in a sink.
  • Spray large plants in a shower.

Physically remove pests

  • Handpick large pests such as earwigs, caterpillars, slugs and millipedes.
  • Small numbers of scale insects can be removed using a fingernail file or something similar.
  • Mealybugs can be removed using tweezers or a cotton swab dipped in alcohol.
  • Some pests can be removed using a forceful spray of water.
  • Repot with new potting soil to eliminate soil-borne pests. Use clean pots and wash soil off plant roots.

Prune

  • Prune if a pest issue is isolated to a few leaves, stems or branches.
  • When infestations are more widespread, prune the most severely infested plant parts. This makes it easier to manage pests on the remaining plant.
  • In the case of severe infestations and depending on the type of plant, cutting it back may help eliminate pests.
  • Watch new growth for signs of infestation.

Throw away or compost the plant

  • Necessary and economical if the plant is heavily infested and badly damaged.
  • Avoids exposing other plants to the same pest problem.

Managing common pests

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CAUTION: Mention of a pesticide or use of a pesticide label is for educational purposes only. Always follow the pesticide label directions attached to the pesticide container you are using. Be sure that the area you wish to treat is listed on the label of the pesticide you intend to use. Remember, the label is the law.

Authors: Jeff Hahn and Julie Weisenhorn, Extension horticulture educator

Reviewed in 2024

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