Beard

A beard is a form of hair growth that forms on a male person's face around the chin area, either with or without a moustache. It usually is grown when a male reaches an adult state. Beards are depicted as a sign of maturity, and can be seen as a symbol of wisdom, experience, authority, power, and (as witnessed with Flowerbell being around Papa Smurf) masculinity. Grandpa Smurf's beard acts as a sort of hammer space for storing important usable items.

In Smurfs Media
Beards are rarely seen among Smurfs since they are usually grown when a male Smurf reaches his 400s, according to the cartoon show. Their beards come in different colors; as seen in the cartoon show, Brainy's beard color is red and Papa Smurf's beard was dark brown when he was younger. However, it is common for other groups of people such as humans, trolls, mermen, and leprechauns to grow and wear beards. In "Symbols Of Wisdom", both Brainy and Gargamel attempted to grow beards through a magic formula, only for their beards to grow ridiculously long, trapping them. It was only through the use of a chili bean and some magical words that these magical beard-growers were freed from their beards.

The "non-canonical" character of Gutsy Smurf is probably the only exception to the rule, as he wears sideburns despite being around the same age as his fellow Smurfs.

Empath: The Luckiest Smurf stories
Beard growth among the male Smurfs in the EMPATH: The Luckiest Smurf story series tends to happen around 300 years of age, though it may not happen for all male Smurfs to be able to grow facial hair. However, Duncan McSmurf and Indiana Smurf are the few Smurfs among Empath's generation of Smurfs who are able to grow facial hair at earlier ages.