A plant cage for supporting growing plants includes horizontal and vertical support rods connected by locking clips to form a cage of a desired size and shape. The locking clip includes a clamp at each end of an elongated body, with each clamp formed of two tabs extending outwardly at oblique angles, with an aperture formed in each tab for receiving a horizontal or vertical support rod. The outwardly extending tabs are resilient and flexible such that the tabs can be moved towards each other to a deflected position so that the apertures align and a support rod can be inserted, the resiliency of the material then biases the tabs away from each other when released so that the apertures become unaligned so that the inserted rod is frictionally captured by the clamp.