Most of the time, we dream of colors because visually we live in a colorful world. However, when those colors become prevalent or unusual in the dream, they may be an interpretive object in themselves. This is especially true if an entire dream setting in is different hues of a particular color or if a significant object seems unique for its coloring.
Since many colors have archetypal feelings and emotions attached to them, the approach taken by Jung is often helpful. However, it may be that a particular color transcends a Jungian meaning because of an experience you have had with it. If Jungian types do not fit, try freely associating significant objects from your waking life with the same color as the dream object for meaning.
Color -- positive meaning (negative meaning)
Blue -- nobility or tranquillity (depression)
Black -- power (death or mourning)
Brown -- Earth, nature (scatological)
Gray -- neutral (passionless, death)
Green -- fertility, renewal, wealth (greed, envy)
Red -- sacrifice, sex (carnality, taboo sex, humiliation, physical injury)
Orange -- adventure, change (forced change, disruptiveness)
Purple -- royalty, positive personal growth (injury)
Yellow -- enlightenment, (cowardice, illness)
White -- purity, wholesomeness, sacred ritual (emptiness)