Although Ben Lam (twice) and Akira Ioane crosed for Auckland to bring the score to 19-17, new coach Scott Waldrom said he wasn't concerned.
"We just kept our composure and Lote kept them level headed."
A Tuimavave cover tackle forced a turnover and captain Greg Foe sealed the victory with Wellington's fourth try.
Waldrom said before the season they had high expectations and were intending to make Wellington a real powerhouse in the sport.
"There's a lot of talent in that young group and they are new to Sevens so to do so well was amazing, though now we have set the standard and we have to keep it up."
The women's final was a nail-biter between the tournament's two best teams.
Selica Winiata scored two tries, her second from exquisite football skills, while Hayley Hutana also crossed for the defending champions.
Hutana later pulled off two cover tackles on dangerous winger Lara Diamond-Brahne just as Auckland were clawing their way back.
"It's great to see our wingers making those spot tackles especially close to our line, that really helped lift the spirits," Winiata said. "We knew Auckland would be physical around the ruck area and we had to make sure we stayed strong on our feet and protect our ball."
New Zealand players Kayla McAlister and Linda Itunu scored for Auckland to bring the score to 14-12 before Winiata's final flourish.
"It is hard to describe, an amazing journey and it comes back to our coaches, our family and our supporters," she said.
The Manawatu men, who had lost to Auckland in extra time earlier in the day, bounced back to beat Bay of Plenty 40-17 in the Plate final.
"It was tough to refocus but we got the job done," said captain Adrian Curry.
North Harbour, with the services of New Zealand Sevens players David Raikuna and Pita Ahki, came from behind to beat Counties-Manukau 28-26 and win the Bowl.
Former New Zealand Sevens player Rory Grice bagged a hattrick as Waikato accounted for Mid Canterbury 34-7 to claim the Shield.
On the women's side Taranaki's rising star Michaela Blyde showed her electric pace scoring two of her team's three tries as they beat Otago 21-12 to win the Plate.
Canterbury were too good for Southland winning the Bowl final 31-7
George Tilsley (Manawatu), who wins the Joe Tauiwi Memorial Trophy, and Hazel Tubic (Counties-Manukau) were named MVP by the respective national coaches, Sir Gordon Tietjens and Sean Horan.
