AAT Bioquest

What are the factors that affect bacterial growth?

Posted March 2, 2023


The four main factors that affect bacterial growth are warmth, moisture, pH levels and oxygen levels. 


Bacterial growth is greatly influenced by the temperature of the environment. Bacteria thrive in warm areas, with the highest growth rate occurring in temperatures close to that of a human body. The rate of growth slows down with cooler temperatures and ceases altogether below certain temperatures. 


Bacteria need consistent water supply to multiply and grow. Fastest bacterial growth occurs in areas that are prone to dampness and stagnant water such as basements and bathrooms. 

Oxygen Levels

Areas with higher oxygen levels provide an ideal environment for bacteria to grow and thrive, while areas with lower oxygen levels can slow down bacterial growth. 

pH Levels

Bacterial growth is greatly impacted by the pH level of an environment. Bacteria grow fastest in environments with neutral pH levels. Growth rate slows down as the pH levels become more basic or acidic and stops altogether at extreme pH levels.

Additional resources

Bacterial growth: a statistical physicist’s guide

Gram Staining

MycoLight™ Rapid Fluorescence Gram-Positive Bacteria Staining Kit