Interfaces of ferroic oxides can show complex magnetic textures which have strong impact on spintronics devices. This has been demonstrated recently for interfaces with insulating antiferromagnets such as BiFeO₃. Here, noncollinear spin textures which can be switched in very low magnetic field are reported for conducting ferromagnetic bilayers of La_0.7Sr_0.3MnO₃-SrRuO₃ (LSMO-SRO). The magnetic order and switching are fundamentally different for bilayers coherently grown in reversed stacking sequence. The SRO top layer forms a persistent exchange spring which is antiferromagnetically coupled to LSMO and drives switching in low fields of a few milliteslas. Density functional theory reveals the crucial impact of the interface termination on the strength of Mn-Ru exchange coupling across the interface. The observation of an exchange spring agrees with ultrastrong coupling for the MnO₂/SrO termination. Our results demonstrate low-field switching of noncollinear spin textures at an interface between conducting oxides, opening a pathway for manipulating and utilizing electron transport phenomena in controlled spin textures at oxide interfaces.