How to Grow Mold

3.5 based on 25 ratings

Updated on Feb 13, 2014

Grade Level: 8th; Type: Microbiology


Students will discover whether mold grows faster in dry or moist conditions.

Research Questions;

How does mold grow?

Most people think of nasty and negative thoughts about mold. But do you know that some types of mold are beneficial? Take penicillium, for example. It is used to produce penicillin, an ingredient needed to make antibiotics which kills off certain kinds of harmful bacteria in the body. And some molds are even edible.

Prolonged exposure to mold may lead to health and respiratory problems in people in weak immune systems and underlying health problems. Most kinds of mold should pose no danger to a healthy individual, especially when only exposed for a short period of time and/or at tiny amounts. However, some types of mold that are caused by flooding and severe water damage may jeopardize health.


  • 3 pieces of expired,stale bread (not moldy yet, but just past the best-by date)
  • 3 plates with a cover
  • A squishy sponge
  • A bathroom (probably the moistest location in the house)
  • Labels & markers
  • Paper and pencil for notes

Recommended for safety

  • safety mask
  • rubber gloves

Experimental Procedure

  • Take one piece of bread and place it flat on a plate, cover with a clear lid. Put a label on the lid (without obstructing your view) and label it “A”. This piece should be left in a dry location.
  • Dampen a sponge and put it on a plate. Set the 2nd piece of bread on top of it and cover. Leave this plate near the 1st. Label it “B”.
  • With the 3rd piece of bread, follow step 1, but instead of placing it at the dry location, take it and place it in the bathroom. Label it as “C”. Please make sure no little hands get to it and no one eats it (but why would anyone...)...!
  • Record your observations for the progression of mold growth day by day for at least 1 week or until you observe a sufficient amount of mold. Are there any differences in mold growth and patterns? Be sure to take photos.
  • After the experiment, record your results. Which piece of bread had the most mold and/or the fastest growth?
  • Properly dispose of the moldy bread after the experiment. Do not consume nor intentionally sniff the mold.


Day 1
Day 2
Day 3
Day 4
Day 5
Day 6
Day 7

Bread #1- Dry

Bread #2- Damp

Bread #3- Condensed Moisture

Terms/Concepts: Mold; Fungi


Mold. (2010, November 6). InWikipedia, The Free Encyclopedia. Retrieved 00:44, November 8, 2010, from

Madigan M; Martinko J (editors). (2005).Brock Biology of Microorganisms(11th ed.). Prentice Hall.ISBN0131443291.OCLC57001814.

Ryan KJ; Ray CG (editors) (2004).Sherris Medical Microbiology(4th ed.). McGraw Hill. pp.633–8.ISBN0838585299.

Jennifer Penn-Chiu is currently a college student with a deep interest in science who is aspiring to become a writer. She writes about all sorts of things across all subjects including, but not limited to; science, crafts, and fashion. She hopes to become a good writer so she can share her thoughts and experiences with the world and future generations.