A Pentas variety designated 99/280-6 is disclosed. The invention relates to the tissue of Pentas clone 99/280-6, to the plants of Pentas 99/280-6, to plant parts of Pentas clone 99/280-6 and to methods for producing a Pentas plant produced by crossing Pentas clone 99/280-6 with itself or with another Pentas variety. The invention also related to the vegetative propagation of Pentas clone 99/280-6. The invention also relates to methods for producing a Pentas plant containing in its genetic material one or more transgenes and to the transgenic Pentas plants and plant parts produced by those methods. This invention also relates to Pentas varieties or breeding varieties and plant parts derived from Pentas clone 99/280-6, to methods for producing other Pentas varieties, lines or plant parts derived from Pentas clone 99/280-6 and to the Pentas plants, varieties, and their parts derived from use of those methods. The invention further relates to hybrid Pentas seeds, plants and plant parts produced by crossing the clone 99/280-6 with another Pentas variety.