Nonu had missed the tackle on TJ Perenara inside the Hurricanes 22-metre area which led to him standing behind his own goal line 12 seconds later watching Beauden Barrett attempt to convert Andre Taylor's eighth try of the season.
The try gave the Hurricanes a 13-12 lead seven minutes before halftime, a lead they never relinquished as they controlled the second half with tries from Julian Savea, Perenara and Jason Eaton.
The match was supposed to be a homecoming of sorts for Nonu, who played more than 100 games for the Hurricanes before being released last year, and scrumhalf Piri Weepu.
Weepu had joined Nonu at the Blues, rejecting the offer of a contract from the Hurricanes, and the partisan crowd did not let him forget it with boos resounding around Wellington Regional Stadium every time he lined up a shot at goal in the first half.
Weepu, however, gradually silenced the cat calls with four successive kicks, which proved to be all of the visitors' points in the first 40 minutes as they wasted a wealth of possession and field position with poor handling and decision making.
Given the Blues' error rate it was hardly surprising three of the Hurricanes' five tries came from mistakes - Taylor's was from a turnover and missed tackle while two others resulted from handling errors by Blues winger George Moala.
The first when he dropped a cross kick from Barrett and Hurricanes captain Conrad Smith pounced on the ball early in the first half.
The second was even worse, when he fumbled a speculative grubber kick from Perenara and the ball bounced to replacement prop Reg Goodes, who barged over though the television match official ruled he had been held up in goal.
Perenara, however, scored the bonus point try from the ensuing scrum to give the Hurricanes a 28-12 lead after Barrett had added the conversion.
Benson Stanley scored a late consolation
try from long range for the Blues before Hurricanes lock Eaton added his
side's fifth in the final minute to complete the scoring.
Hurricanes:
15 Andre Taylor, 14 Cory Jane, 13 Conrad Smith (captain), 12 Tim Bateman, 11 Julian Savea, 10 Beauden Barrett, 9 TJ Perenara, 8 Victor Vito, 7 Karl Lowe, 6 Faifili Levave, 5 Jason Eaton, 4 Jeremy Thrush, 3 Jeffery Toomaga-Allen, 2 Dane Coles, 1 Ben May
Substitutes: 16 Motu Matu'u, 17 Reg Goodes, 18 Jack Lam, 19 Brad Shields, 20 Chris Eaton, 21 Charlie Ngatai, 22 Alapati Leiua.
Blues:
15 Hadleigh Parkes, 14 Rene Ranger, 13 Benson Stanley, 12 Ma'a Nonu, 11 George Moala, 10 Michael Hobbs, 9 Piri Weepu, 8 Peter Saili, 7 Luke Braid (captain), 6 Chris Lowrey, 5 Ali Williams, 4 Filo Paulo, 3 Charlie Faumuina, 2 Tom McCartney, 1 Tevita Mailau
Substitutes: 16 James Parsons, 17 Angus Ta'avao, 18 Liaki Moli, 19 Daniel Braid, 20 Alby Mathewson, 21 Lachie Munro, 22 David Raikuna