How to Control Bugs in Potting Soil


Bugs in potting soil and their eggs are best controlled before using the soil. Sterilizing the soil in an oven is the best method for killing off the small pests. While you can use a microwave oven, the most effective heating method is using a conventional oven. Large amounts of potting soil can be placed in large, heat-resistant pans. When complete, the potting soil is free of insects, eggs and weed seeds.

Step 1

Layer the potting soil in a shallow, oven-rated pan no more than 4 inches deep.

Step 2

Cover the pan tightly with a single layer of aluminum foil. Seal the edges of the foil to the sides of the pan.

Step 3

Insert the oven thermometer deep into the soil through the aluminum foil in the center of the pan.

Step 4

Set the oven to between 180 and 200 degrees Fahrenheit.

Step 5

Heat the soil for 30 minutes once the thermometer has reached 180 degrees.

Step 6

Turn the oven off. Allow the soil to cool. Remove the pan from the oven. Use the soil immediately or keep it covered to use later. The aluminum foil cover will keep out insects from the sterilized soil.

Tips and Warnings

  • Do not allow the soil to get above 200 degrees Fahrenheit, as this may produce plant toxins in the soil.

Things You'll Need

  • Oven-rated pan or container
  • Aluminum foil
  • Oven thermometer


  • University of Minnesota Extension: Houseplant Insect Control
  • Colorado State University: Start Seeds and Plants in Sterilized Soil
Keywords: sterilize soil, killing pests, potting soil, kill bugs in soil

About this Author

G. K. Bayne is a freelance writer, currently writing for Demand Studios where her expertise in back-to-basics, computers and electrical equipment are the basis of her body of work. Bayne began her writing career in 1975 and has written for Demand since 2007.