Shamrocks and clovers are not just for March- you can wear clovers anytime. Included with the hat pattern are graphs for some other optional shamrock/clover themed ideas. Small enough to work into most patterns, these motifs can be done in any color or worked into a knit/purl alternating pattern. The choice is up to you!
The hat is only worked in two colors, but any number of colors may be used.