Abstract: A supporting frame for a portion of a stem of a plant comprises a generally arc-shaped guiding member, two spacers projecting away from an inside concave surface of the guiding member, and a pressing member pivotally connected to the spacers. The guiding member, the pressing member and each spacer define a U-shaped cross-section for permitting insertion of the portion of the stem therein. The pressing member is deformable between an open position and a closed position. In the open position, the pressing member is away from the guiding member and the portion of the stem can be inserted between the guiding member and the pressing member.