Nutrient Agar is used for cultivating a wide variety of nonfastidious organisms. Description: Nutrient Agar was suggested by the American Public Health Association (APHA) in the early 1900's as a standard culture medium for use in bacterial processing in water analysis. This is recommonded for the bacterial examination of water milk. It now continues to be a widely used general purpose medium for growing nonfastidious organisms. It is specified in many standard methods procedures for examining foods, dairy products, water, and other materials.