Many fans of the show know that Michael Landon was very concerned about his status as not only a family man but also a sex symbol, noted by the numerous appearances Landon appeared on the show shirtless. But Landon reportedly began to go prematurely grey while he was still in his 20s and starring on Bonanza.
When he started going grey, he began dying his hair using Clairol hair dye – namely the color Medium Ash Brown. But that had the added effect of the long days in the sun on set turned his hair more a faded lavender due to the underlying light colored grey. In the end, he would have his hair professionally dyed instead of using an at-home coloring kit.