“Elves and Dragons. Cabbages and potatoes are better for me and you. Don't go getting mixed up in the business of your betters, or you'll land in trouble too big for you..."

—Hamfast telling others what he told Sam

Hamfast was born in 2926, the third son of Hobson Gamgee, who was a roper.

He became a gardener by entering the service of Holman Greenhand. One of his first jobs was tending the garden of Bag End, he and Holman tried frantically to keep the garden in order during the auction of the presumed-dead Bilbo Baggins. It is likely that at this time he already lived at Number 3, Bagshot Row.

Later he became a gardener in his own right and a local expert on potatoes. He married Bell Goodchild, and they had six children: Hamson, Halfred, Daisy, May, Samwise and Marigold. His son Sam became his apprentice.

Sam took over most of his father's work, who had become too old for the laborous work. He became known as the "Gaffer", a name Sam uses more often than "Hamfast".

Prior to the Farewell Party, the Gaffer entertained a crowd at the Ivy Bush. Always a man of loquacity and knowledge, he argued with Sandyman, Old Noakes and Ham's neighbor Daddy Twofoot about the Bagginses and the Sackville-Bagginses.

On the night of the departure of Frodo and Sam from the Shire one of the Nazgûl rode up the lane, and asked the elderly hobbit about "Baggins". A week later, he was visited by Gandalfwho also informed about Frodo's whereabouts.

When Lotho and Saruman took over the Shire, he was evicted from Bagshot Row.  After the Battle of Bywater, in which he only had a marginal role, he moved back into the newly restored New Row, while Sam moved into Bag End.