On the surface, color may seem like one of the simplest components to use in the design process. However this can be deceiving. Since color has such a significant influence on what we perceive visually, it is important to take a good deal of consideration into your choices.
Color and contrast also can be used to highlight focus in a design, and as a directive map for the viewers eye. For my example below, the striking green of the leaf makes it stand out against the more mundane backdrop. The focus of the image is clearly on the shape and form of the leaf in the foreground.
However in this next photo, despite the fact that it employs and almost identical color scheme, the effect and focus are quite different. The collection of leaves and lack of clear distinction between figure and ground come together to form a very different image.
While the two share some similarities in temperature and color, the composition and color is very different. The second could almost pass a standalone texture/pattern, especially if one was to remove the bright spot peeking through on the left side of the image.
Another reason I chose these two images is to show how little color is needed to create an effect. Basically only three colors are used in each one (green, dark brown, and bright white). However they still work to create a visually intriguing picture, and one could imagine seeing these images used to convey or advertise for a variety of purposes.
As with any design component, color is most powerful when used responsibly. As evidenced above one does not need an inane amount of it to create interesting images, however it can be very interesting to play around with multiple colors and their interactions to create your desired effect.