Garrard came from a family of artists who were descended from Marcus Gheeraerts the Younger (c.1561-1636). He was a pupil of Sawrey Gilpin (1733-1807) whose daughter Matilda he married. He studied at the R.A. Schools from 1778 and was a frequent exhibitor there from 1783-1826, becoming an ARA in 1800. Garrard specialised in animal portraiture and sculpture, but also painted landscapes, portraits and urban views. From 1795 he worked increasingly as a sculptor.

He died in Brompton, then a village next to Knightsbridge. where many artists lived.