To grow mold on fruit, place the fruit inside a sealed plastic bag, and place the bag in a humid storage space. The combination of the humidity and the lack of exposure to fresh air helps mold grow quickly.
- Choose fruit that is most likely to develop mold quickly
Select fruit that has a soft, squishy exterior, such as strawberries or raspberries. Do not choose fruit that has a harder exterior, like apples, grapefruit or bananas, as the peel keeps mold from forming as quickly.
- Select a moist environment for the fruit
Choose a room that experiences a great deal of humidity. If you are in a house, the bathroom is usually the most humid, as the steam from showers and baths adds to the moisture in the space.
- Seal the fruit securely
Place the fruit inside a zip-top storage bag, and seal the bag securely, leaving no gaps along the closure line. Set the fruit on a shelf in the chose room, and give the mold a few days to form. Watch for the formation of green or white wispy growths on the fruit, as these are the first signs that mold is growing. Discard the fruit after you have finished growing the mold, as it is not safe to eat.