How wet should I keep my Venus flytrap soil during dormancy?

If you used the tray method for watering your Venus flytrap during the active growing season, then you should remove the Venus flytrap from the tray for dormancy.

The plant can just be top watered and only enough to thoroughly moisten the media and then allowed to dry to the point where the soil is just barely damp before watering again. Any extra water should be allowed to just run out the bottom. The plant shouldn’t be allowed to stand in water. This will help prevent fungus and root rot from starting.

Overwatering, especially during the winter, is the leading cause of death for Venus flytraps in cultivation.