Unhappy with their own first-half effort with balls spilled over the sideline and being driven backwards over their line by the Ratana pack, Border began to string consecutive phases together and crossed for five well-taken tries, scoring twice inside the final five minutes as the home team ran out of legs.
"Tough battle at the start - niggly," said Border coach Ross Williams.
"Proud of the way we stuck to what we wanted to do, and moved the ball into space.
"We had fun, that's the pleasing thing."
Knowing he needed a big match against Ratana's heavyweights, prop Kamipeli Latu was outstanding, while Williams also praised tryscoring first-five Jack Lupton for a strong match after he went missing in the loss to Integrity Motors Pirates the previous week.
Second-five Poasa Waqanibau stood out in the first half while his team were still scratching around - making some powerful bursts and laying on the opening try to flanker Sikeli Ulukuta.
Ratana coach Cornel Mason could only shake his head in frustration.
"Same thing as usual, interpretations of the referee's rules ... we dominated the set piece. The last is our discipline, I truly believe that's where we're lacking ... that's what we ask of them. We've got to learn from this."
While they had the territory, Border were not executing through the first quarter, as they infringed at ruck time, fullback Fraser Middleton slipped in the mud while new hooker Drew Young, covering the injured Cole Baldwin, had trouble getting the lineout throws straight.
Lock Jack Hodges, only recently back from leg injury, limping off after 10 minutes was also a concern.
Waqanibau finally busted the line and found the equally quick Ulukuta on his outside for the opening try.
Working forward off a series of penalty lineouts, Ratana drove Border back in vintage style with Mete going over to make it 7-7 after 26 minutes.
Waqanibau kept attacking but Border squandered his work with penalties and dropped ball.
The heat was rising for both sides and when Mete and Madams went, Lupton made it 10-7 right on the break.
Border then began to finally put it together as Latu and centre Anaru Haerewa took on the line, then Waqanibau had a crack and halfback Lindsay Horrocks shot through a half gap.
At the line, Latu showed great strength to get the ball down and sap Ratana morale at 17-7.
Mikaere Penetito then went to the bin as a five-man Ratana pack struggled on.
Waqanibau chip kicked in his 22m and Horrocks made a great tackle as Border's pack drove over to regain the ball, before kicking ahead, with No8 Kieran Hussey winning the foot race.
Winger Tom Symes defused a midfield Ratana bomb and stepped past two tacklers to race 60m for the bonus point try.
Another Symes run brought them back on attack and Middleton spread to the overlap, with prop Andrew Retallick diving over out wide before Lupton scooted over.
He also kicked the final conversion after Haerewa kept the ball on the toe to score, following a Horrocks chip and Ulukuta grubber kick.