Hesston is a city in Harvey County, Kansas, United States. As of the 2020 census, the population of the city was 3,505. Large manufacturing fa…Hesston is a city in Harvey County, Kansas, United States. As of the 2020 census, the population of the city was 3,505. Large manufacturing facilities for AGCO and Stanley Black & Decker are located in Hesston. It is home of Hesston College.