  We demonstrate that a quasi-two-dimensional spin-1 condensate quenched to a
ferromagnetic phase undergoes universal coarsening in its late time dynamics.
The quench can be implemented by a sudden change in the applied magnetic field
and, depending on the final value, the ferromagnetic phase has easy-axis
(Ising) or easy-plane (XY) symmetry, with different dynamical critical
exponents. Our results for the easy-plane phase reveal a fractal domain
structure and the crucial role of polar-core spin vortices in the coarsening
dynamics.
