How Does Mold Grow?

Have you ever observed fungus on expired bread or the areas where there is a lot of moisture? Well, it is basically a fungal growth that is found in wet areas. It can be on food items, walls, ceilings, etc. How does mold grow? Children might have this question in their minds. Therefore, you can conduct science experiments for kids to teach the reason behind the growth of mold. This is one of the best science project ideas for kids. 


Young children must have seen the molds in their house or the surroundings. But, they might not know what it is and what is the reason for its appearance. How does mold grow? This is what children want to know about mold. You can use affordable and kid-friendly materials to teach children on how mold grows. Learning the phenomenon will help children to gain scientific knowledge and enhance their observational skills.  

What is a Mold?

Mold is a fungal growth that grows in wet or moist areas. These are reproduced by tiny spores. These spores grow when there is adequate moisture, temperature and nutrients to grow into a mold. These are commonly found in a place where there is a lot of moisture. You can also see molds on old buildings, ponds, wells, expired food items, etc. The excess moisture due to leakage, plumbing issues, floods, etc., leads to the formation of mold. There are different types of molds found in the environment, such as Rhizopus stolonifer, Penicillin, Aspergillus, etc. 

Factors Responsible for Mold Growth 

It is also stated that mold can cause health issues in humans in the form of allergies and respiratory problems. Molds basically rely on organic matter for their energy. How does mold grow? To know that, you need to understand the factors responsible for the growth of mold. The factors that contribute to its growth are mentioned below:

  • Food: The mold grows on substances that it can digest. It cannot digest concrete or metal surfaces. 
  • Oxygen: The mold needs oxygen to survive. 
  • Water: The mold grows in areas that are wet, damp and humid. 
  • Temperature: The mold needs adequate temperature to grow. For example, it grows between 77o and 86o F. 

Fun Facts about Mold

  • It is found everywhere and helps in the decomposition of organic matter.
  • It is grown between 24 to 48 hours.
  • It cannot be killed with bleach.
  • There are around 10,000 species of molds found in the environment.
  • It can cause severe health problems in humans such as fatigue, respiratory problems, skin irritations, etc. 
  • The growth of the mold can be prevented. 
  • It grows in moist, damp and wet areas. 
  • It is visible in the areas where there is leakage of pipes and expired food items such as bread. 
  • Some of the molds are used as a fermenting agent. 
  • It contributes to sinus problems in humans. 
  • It cannot grow on surface areas such as concrete, glass, rocks, stones, etc. 
  • It spreads by spores to form new colonies. 
  • It destroys wood more than fire and termites. 
  • It does not need light to grow. 
  • It is found in households today more than it used to 50 years ago. 

Easy Science Project: How Does Mold Grow?

Learning about mold enables children to understand its appearance and the factors that are responsible for its growth. You can show children the areas where mold is grown using protection gears. Having said that, they will have close observation of the mold and learn about them effectively. To make it easier for children, you can assist them in growing molds as a science project. Children will show a lot of excitement to perform science experiments that teach them about mold. Check out the procedure given below.

How Does Mold Grow?

Aim of the Project

To observe the growth of mold in moist and dry conditions, you can perform this experiment at home.  Also, understand the factors responsible for its growth, such as temperature, water, oxygen, nutrients, etc. 

Material Required  

  • Three to four slices of bread
  • Two plates
  • Gloves
  • Safety mask
  • A paper
  • A pen or a pencil


  • Take a slice of bread and keep it on a plate labeling it as DRY. Cover the plate with a lid and keep it aside in a dry place for five days.
  • Take another slice of bread and place it on a damp plate. Cover the lid and label it as WET. Keep the plate aside for five days. 
  • Then, take plate DRY and plate WET using gloves after five days to check the growth of the mold on the plates.
  • Take a sheet of paper and record which plate has the fastest growth of mold after five days. 
  • Close the lid of the two plates and leave it for five more days. 
  • After five days, open the lid of the plates using gloves and observe the fungal growth.
  • Record the highest growth among the two plates on a sheet of paper.


The slice of bread kept in a plate WET was found to have the highest amount of mold compared to the ones kept in a dry place. It concludes that the growth of mold is fastest when the area is wet and damped.

Benefits of Learning How Does Mold Grow?

The benefits of learning about the growth of mold are mentioned below: 

  • It helps children learn about the factors that affect growth of mold.
  • It enables children to perform simple science experiments related to mold growth. 
  • It helps them understand the reason behind its growth. 
  • It develops observational and analytical skills in children.
  • It creates interest in children to perform science experiments. 
  • It enables children to know where and how the mold is grown. 
  • It helps children in learning about the importance of mold growth for the environment. 
  • It creates awareness about health issues that can occur due to mold. 
  • It enables children to learn and come up with science project ideas related to mold.

To know more information, explore science games for kids, STEM activities for kids, science activities for preschoolers in the kids learning section at Osmo.

Frequently Asked Questions on How Does Mold Grow?

How does mold grow?

Mold is grown in moist, damp and wet areas. The factors responsible for the growth of mold are temperature, water, oxygen and food.

What are the benefits of learning how mold grows?

The benefits of learning about mold is that it helps children learn and understand the scientific reason behind the growth of mold. With this knowledge, they can get many science project ideas that enable them to perform science experiments related to mold. Most importantly, children will develop observational, problem-solving and critical thinking skills.