(Photo/Jeff Hahn UMN-Extension)

Talking Plants

Jillian Patrie | University of Minnesota Yard and Garden Extension

Controlling pests indoors during the winter months can be a difficult task, taking a toll on plants and you at the same time.  A common pest that is efficient at staying hidden until they become a houseplant emergency are mealybugs.  These soft-bodied insects look like tiny pieces of cotton or sometimes dust until you look a little closer.
Their bodies are covered in a waxy and powdery-like secretion that also makes it hard to control them with insecticides.  Mealybugs use sucking mouthparts to feed on plant sap, causing yellow leaves, stunted growth and wilting plants.  Besides identifying the mealybug itself, look for a shiny, sticky substance on leaves and stems called honeydew.  Mealybugs like to hide along leaf veins, on the underside of leaves and where leaves join the stem.  Mealybugs can live in the soil or on the underside of pots too, so be sure to check those spaces as well.
How can we get rid of these pesky little furballs?  Catching mealybugs early before populations become large can help with controlling them effectively.  Because they like to hide in hard-to-reach places, inspecting plants regularly can be a way to catch the issue early.  Be sure to inspect new additions to your houseplant collection before placing them next to current plants.  Mealybugs can’t fly, but they can spread from one plant to another especially when they are close or touching.
Washing plant parts that have mealybugs is the first step to removing them, you can also use a paper towel or rag to gently wipe them off.  If populations are low, using a cotton swab dipped in alcohol and touching each mealybug individually will work too.  If populations are high, the cotton swab method can be tedious, so pesticides may be the solution.  Pyrethrin is a natural pesticide that is derived from chrysanthemum plants and can be effective for mealybug control.  Permethrin is another pesticide active ingredient that can be used for managing mealybug outbreaks. Some pesticides can be smelly when used indoors. If space allows, apply pesticides in a well-ventilated area.  When using insecticides, ALWAYS read the label and follow use instructions.
In some cases when mealybug populations are numerous and treatment efforts have not been effective, it may be necessary to discard the houseplant.  This is not always an easy decision, but don’t feel defeated if this is the route that is the best for your situation.  Growing plants is all about trial and error and there are always more plants at the store!
For more information about controlling houseplant pests visit https://extension.umn.edu/product-and-houseplant-pests/insects-indoor-plants.
Please join The University of Minnesota Agricultural Business Management Team for “Farm Business Transition: Where do I begin? This workshop will cover topics related to farms transitioning to new hands and estate planning.
Thursday, March 20th, 2025
10:00 am to 3:00 pm (lunch provided)
RDO, Hawley, MN
To register please visit https://extension.umn.edu/event/farm-transition-and-estate-planning-hawley
Or call Heather Dufault (218-280-1129) or Jillian Patrie (218-299-7338)
For questions about this article or local assistance please contact Clay County Extension Educator Jillian Patrie at 218-299-7338 or by email at patri350@umn.edu.