Expert: Christopher Littrell - 9/30/2007

Question
I live in Canada and the winters are very cold. I want to put my Venus fly trap into dormancy and i read that you could put it in a refrigerator. is this true?

Answer
Hello Paul,

Yes, it is possible to place a Venus Flytrap in the refrigerator, not the freezer though, during its dormancy period. If you have a cold room or garage, or simply a window in your home that allows a cold draft of air down to about 40 degrees (something likely in the cold winters in Canada), you can simply place the plant there. Make sure that wherever you place it it will not freeze solid or experience wind that could freeze dry it.

If the plant has been getting full sun over the growing season you can simply leave the plant where it can get sun until the fall photoperiods have reduced enough to tell the plant that winter is coming. This is generally during November when the day length shortens down to about 8 hours or less or good sunlight. If you are already experiencing very cold weather there, bring the plant in and place it in a window where it receives as much sun as possible and just let it go dormant there. If the window feels very cold to the touch and you feel a cold chill near the window, it should be fine to overwinter the plant there. Just keep watering it about half as much as normal, keeping the soil barely moist at all times, and keep a lookout for mold growing on the plant or soil. If you notice mold growing, use neem oil or sulfur based fungicides to kill the fungus, never soap based products or anything with copper in it.

When the days begin to lengthen, you can let the plant come out of dormancy in the window until winter cold has passed, then place the plant back outside where it can get full sun. Next year you should see a flower scape a month or two after it comes out of dormancy.

If you choose the refrigerator method you will simply have to wait until the plant has experienced fall photoperiod shifts, then place it in the fridge in a plastic bag that is slightly open to allow air in. Check the plant every few days to inspect it for mold and keep it watered enough just to moisten its soil. In spring, bring it out of the fridge and place it in a strongly lit window and let it come out of dormancy there until cold weather has passed, then place it back outside again.

This can also be done with an ice chest that is opened in the day for about 8 hours to air it out and give the plant some light. You would have to place frozen water bottles around the plant to bring the temperatures down to 40 degrees when the chest is closed and replace the bottles every 12 hours. It takes more work, but keeps the plant mold free in my experience (keep a lookout for mold anyways as the ice chest is still a stagnant place when it is closed).

Keep up the good care with your Venus Flytrap.

Christopher