Place a 1-inch layer of gravel in a pot one size larger than the previous gloxinia container. Use a shallow pot with a depth of approximately 6 inches.
Combine 1 part loam, 1 part peat and 1 part coarse sand. Fill the pot half-full with this potting medium.
Lift the gloxinia tuber out of the old pot. Brush off the excess soil and set the tuber on top the soil in the new pot so the indented side faces up.
Add potting mix to the pot until the top of the tuber sits 1/2 inch beneath the soil surface. Water the mix until it is evenly moist throughout.
Keep the pot in a 60 to 70 degree Fahrenheit location and away from direct sunlight. Water often enough so that the soil doesn't dry out completely. New growth appears within two to four weeks.