Someone could say "the ripe old age of 19"... but this is a little bit sarcastic. "Ripe old age" is primarily used when talking about someone who is very old. Using it to refer to someone who is 19, probably has something to do with them making fun of a 19 year old's self perceived experience, when really most people would see them as just a baby. :P

Hi. If you say at the ripe old age of 19 you are being sarcastic, since 19 is hardly old.normally we would say something like he started learning Chinese characters at the ripe old age of 80. It is a hard task and especially at 80.