Prill heads having prilling assemblies that include adjustable openings. Prilling methods using the prilling assemblies can allow for the size of the openings to be varied during processing to alter the size of the prills as desired, or for clogged openings to be cleared, while maintaining operation of the prilling process. The prilling assemblies and prilling methods can be used to produce fertilizer products, including fertilizers comprising ammonium sulfate nitrate.
