The device is made of a slightly elastic steel band bent into a circular shape (3) with a hook (15) at one end and two longitudinal cuts (7) located at the opposite end. The two outer tongues (11) created by the cuts (7) are bent upwards (13) at their outer ends, the central tongue (9) is of a straight shape. The branch of the plant to be trained is inserted into the circular space (1) and kept in place by the elastic quality of the material, the wire is pushed along the lower surface of the central tongue (9) until it engages with the hooks (13) at the ends of the outer tongues (11). The central tongue (9) acts as a locking element.