Putative transcription factor. Probably involved in the regulation of floral induction. Homo- and heterodimer with other ZFHD proteins. Interacts with ZHD1, ZHD2, ZHD5, ZHD7, ZHD8, ZHD10 and ZHD11. Mostly expressed in flowers and inflorescence. Not detected in the meristem prior to exposure to long days (LDs), but after exposure to three LDs, stable accumulation on the flanks of the meristem adjacent to floral primordia, during floral induction. Induced by exposure to long days. The homeodomain differs form the typical one by having namely 4 instead of 3 extra amino acids inserted in the loop between helix 1 and helix 2.