A closing wheel assembly is provided for a seed row planter unit (10) behind the gauge wheel (19) assembly and furrow disks (17) of the planter unit. The closing wheel assembly includes a coupler (18) with a pair of closing wheels (20) mounted thereon. A single pin (38) removably extends through the coupler and through the gauge wheel assembly to detachably mount the closing wheel assembly to the gauge wheel assembly. Different closing wheel assemblies can be quickly mounted on the row unit, depending upon the type of seed being planted. The closing wheels (20) are laterally adjustable via a rotatable threaded bushing (52) so as to be centered behind the furrow disks (17).
