Most guitar players look at the 5 string banjo as a completely new instrument. Something that you would need to learn a completely new tuning and approach to playing. This is incorrect. Actually the guitar and the 5 string banjo are tuned very similarly, and you can easily bring many of your guitar licks directly over to the 5 string banjo.
Fred Cale talks about and explains this in a very clear way in the video below. He shows you how the same open G triad you find on the guitar, you can find on the 5 string banjo. This allows him to bring his guitar licks over to the 5 string banjo and can help him break out of the bluegrass box that many banjo players put themselves in.