How to Grow a Venus Fly Trap in a Flask


A Venus flytrap (Dionaea muscipula) is carnivorous plant that derives a fair amount of its nutrients from snap-trapping and digesting insects and spiders. It is native to the bogs and savannas of North and South Carolina. A common misconception--perhaps based on the plant's alien appearance--leads hobbyists to believe that it is a tropical plant. This is untrue, and, in fact, Venus flytraps require winter dormancy to grow strong and healthy.

Step 1

Fill the bottom 1/4 of the flask with a soil mix of potting soil, builder's sand and sphagnum moss or peat. Use a paint stirrer to mix the ingredients inside the flask and also to loosen the planting medium.

Step 2

Insert the rhizome through the neck of the flask. Gently manipulate it with the paint stirrer so that the rooted side faces down. Carefully press down on the rhizome until it sinks into the loose soil.

Step 3

Add more soil to the flask slowly and until the top of the rhizome is level with the soil.

Step 4

Fill the spray bottle with lukewarm water and spray the soil containing the rhizome.

Step 5

Place the flask on a windowsill where it gets about two hours of sun exposure each day.

Step 6

Increase the humidity and warmth inside the flask with frequent spraying of water. When using a Buechner flask, consider closing the hose barb with a stopper to prevent too much airflow. Rely on a thermometer to reach an air temperature that falls between 70 and 95 degrees F.

Step 7

Catch and feed live prey once the plant develops its snap traps. Choose only bugs that are smaller than the traps. Pick up the live prey with tweezers and drop it into the flask through the opening at the top. Do this at a rate of two insects per month. Briefly place a stopper on the flask to prevent escape. Remove the stopper as soon as the bug is trapped.

Tips and Warnings

  • Do not feed insects that are too big for the plant, or the struggling bug might harm the snap traps. Additionally, large insects prevent the traps from closing completely, which can lead to bacterial buildup and rot on the carapace of the expired insect.

Things You'll Need

  • Erlenmeyer or Buechner flask
  • Soil mix
  • Paint stirrer
  • Venus flytrap rhizome
  • Spray bottle
  • Lukewarm water
  • Thermometer
  • Tweezers
  • Live prey
  • Stopper


  • Botanical Society of America: The Mysterious Venus Flytrap (Propagation)
  • The Garden Helper: The Venus Fly Trap (Soil Options)

Who Can Help

  • The International Carnivorous Plant Society, Barry Rice: The Carnivorous Plant FAQ
  • "Scientific American;" How Does the Venus Flytrap Digest Flies?; Aug. 19,2002
Keywords: Venus flytrap, Dionaea muscipula, flytrap Erlenmeyer flask, flytrap snap traps

About this Author

Based in the Los Angeles area, Sylvia Cochran is a seasoned freelance writer focusing on home and garden, travel and parenting articles. Her work has appeared in "Families Online Magazine" and assorted print and Internet publications.