Georgia Plimmer belted a career-best 147 off 139 and Leigh Kasperek 89 off 98.
Knight took 1-43 off six overs.
Northern were dismissed for 171 in the 42nd over to lose by 145 runs, with Knight making seven off 36 balls.
Northern are sitting fourth on the six-team table on seven points.
Their opening match against Auckland in Whangarei on November 18 was abandoned and Auckland beat them by 60 runs on the Duckworth-Lewis-Stern method the following day.
Knight took 3-32 off seven overs in that match.
Northern are next in action against Canterbury Magicians at Mt Maunganui on Saturday, December 9.