A novel garden bean cultivar, designated H28122, is disclosed. The invention relates to the seeds of garden bean cultivar H28122, to the plants of garden bean line H28122 and to methods for producing a bean plant by crossing the cultivar H28122 with itself or another bean line. The invention further relates to methods for producing a bean plant containing in its genetic material one or more transgenes and to the transgenic plants produced by that method and to methods for producing other garden bean lines derived from the cultivar H28122.