Infants soon after birth have limited color vision, and they have trouble discriminating blues from greens and reds from yellows. By 2 months, most babies can discriminate among basic colors.
Brown, A. M. (1990). Development of visual sensitivity to light and color vision in human infants: A critical review. Vision Research, 30, 1159
Shelov, S. P. (Editor-in-Chief). (2004). Caring For Your Baby and Young Child: Birth to Age 5. The American Academy of Pediatrics. Revised edition. New York: Bantam Books.