Petri dishe with cetrimide agar. Pseudomonas aeruginosa growing on cetrimide agar. Cultivation 24 hours at 37°C + 72 hours at room temperature.

Pseudomonas aeruginosa produces a number of water-soluble pigments. When the yellow-green pyoverdine combines with the blue water-soluble pigment pyocyanin, the bright green color characteristic of Pseudomonas aeruginosa is created.