The spectrum of visible light for honey bees is shifted toward the ultraviolet end. They see things that we can’t in the shorter ultraviolet wave lengths. On the other hand, bees don’t see red. A red flower appears to them as a black spot.
Many flowers have patterns on their petals that reflect ultraviolet light. These patterns have evolved to attract bees, and also to help them find the nectar in a flower. These patterns, called honey guides, may appear as rays or spots leading into the interior of the flower.
According to Jürgen Tautz in his book The Buzz about Bees, bees are quite skilled at discriminating between colors as they approach flowers, but have more trouble discerning colors once they leave a feeding site and head back home. However, patterns are another matter. Bees can discriminate between patterns whether they are approaching a field of flowers or approaching their home hive.
Tautz writes that a row of brightly colored hives each of a different color—say one green, one red, one yellow, one blue—doesn’t aid the bee in finding the correct hive. But hives painted with colorful distinguishing patterns, especially around the hive entrance, can help the bees find the right home.