Published : Sunday, 2 June, 2019 at 12:22 AM, Update: 03.06.2019 3:21:46 AM, Count : 53
Kiwi opener Martin Guptill then smashed an unbeaten 51-ball 73, while Colin Munro made 58 not out to help the New Zealanders reach their target in less than 17 overs.
Earlier, Kiwis skipper Kane Williamson won the toss and chose to bowl on a pitch so green it was indistinguishable from the outfield, and he was rewarded when Henry trapped Lankan opener Lahiru Thirimanne leg-before in the first over.
Canterbury seamer Henry, who conceded 107 runs in a warm-up match against West Indies earlier this week, continued his resurgence to remove Kusal Perera and Kusal Mendis in the ninth over to leave the Sri Lankan middle order exposed at 46-3.
"Good to go out there on a green surface," Henry, who credited his stint with English county Kent last season for his man-of-the-match performance, said after the match.
"You don't get too many one-day wickets like that. On a surface like that we were trying the full length and get them forward, with them trying to hit us off our length."
Henry took 3-29 off seven overs, while Ferguson bagged three middle-order wickets as Sri Lanka finished with the lowest ODI total at Sophia Gardens - below their own record there of 138, also set against the Kiwis, in the 2013 Champions Trophy.
Sri Lankan captain Dimuth Karunaratne led a mini-recovery for his side, carrying his bat with an unbeaten 52 to take the total past 100.
But apart from all-rounder Thisara Perera (27), he received no support from the lower order as they were skittled out with 20.4 overs to spare.
Karunaratne has urged his team to reassess their approach for the rest of their campaign after the majority of the batsmen perished in search of early boundaries.
"136 is never going to be enough in these conditions," the Sri Lankan captain said.
"It was a good toss to win... it was seaming and swinging in the morning, so they had the advantage.
"We need to think about our game and approach. We're trying to play our shots early, we need to give ourselves a chance to get set and then score runs."
The result cemented 2015 runners-up New Zealand's status as the dark horses in the tournament and also highlighted why Sri Lanka, who have recorded just one ODI win in 2019, may struggle to qualify for the semi-finals.
New Zealand's next game is against Bangladesh at The Oval on Wednesday, while Sri Lanka stay in Cardiff to play Afghanistan on Tuesday.