Garwood is a borough in Union County, New Jersey, United States. As of the United States 2000 Census, the borough population was 4,153. Garwood was incorporated as a borough on March 19, 1903, from portions of Cranford Township and Westfield Town. In the north side of Garwood, most of the streets are numbered, while in the south side of Garwood most of the streets are named after trees.