True neutral colors are white, black, brown and gray. If you remember mixing all your crayon colors together as a kid, you likely came up with some shade of brown. Brown works well with other colors, because whatever color you pair it with is hidden somewhere in the color brown. Scientifically speaking, black is the absence of all colors and therefore can't clash with another shade, while white is the sum of all colors and therefore works in concert with other shades. Gray works as a neutral simply because it's a combination of black and white.
Cool colors are like those you might see on a mountain vista: blue, green and lilac. Shades of blue are calming, tranquil and serene. They automatically soothe people, which explains why so many bedrooms and offices are painted in shades of blue. The color blue can do the same thing for the exterior of your home, either as the main color or as an accent tone.
Neutral shades are a safe bet when it comes to finding a color that coordinates with blue, but there are other color combinations that work as well. If you want a funky, modern look, pair blue with orange. Because orange is directly across from blue on the color wheel and has no base color in common with blue, it's considered complementary. For a slightly more traditional and harmonious color combination, try a shade of green or purple. These colors work with blue because they have something in common. Green is a mixture of blue and yellow, while purple is a blend of blue and red. Finally, you can go with a monochromatic color scheme by using one shade of blue for the body of the house and another shade for the trim, shutters and door.
There are shades that lend themselves to being mixed with blue, that are enhanced by adding a blue tint. Blue, red and yellow are the primary colors. Secondary colors are those shades that result from mixing two of these primary colors together. You can add blue to any secondary color to give it more punch and to emphasize the blue shade. You can also add blue to a neutral color for a hint of the hue. Blue-gray offers a traditional exterior shade, while a touch of blue in white paint adds a sense of depth to the color.