An attachment device for coupling a floral arrangement to an article such as a lapel of a jacket, a floral apparatus that includes at least a portion of the attachment device and the floral arrangement, and a method of assembling such a floral apparatus. The attachment device may include a support element and a retaining element that are detachably coupled together. The support element includes a rib member and first and second posts extending from a bottom surface of the rib member in a spaced apart manner. The rib member and the first and second posts collectively define a receiving cavity that is configured to receive a portion of a stem of a floral arrangement. The retaining element includes one or more pins that extend into the rib member of the support element to couple the retaining element to the support element.