A magnificent unbeaten partnership of 152 between Ben Kohler and Adam Spooner guided Vale from a perilous position to what was ultimately a comfortable six-wicket triumph, with almost 14 overs to spare.
Chasing a target of 199 to win, Vale were in trouble early on. The top four batsmen in the order - Steven Reingold, Alex Haffner, Grant Reingold and Benjamin Lederman - had all departed, leaving Watford Town sniffing an early finish with the score at 50-4.
However, Kohler and Spooner then came together to wrestle control back and guide LMV over the finishing line, both youngsters displaying mature heads that belied their relative youth.
Spooner was composure personified in making a chanceless 56 not out, his finest innings for the club.
Kohler combined punishment and common sense in equal measure, deflating the home side's bowlers with his intelligent batting. He finished with 78 not out, made from just 63 balls and featuring 10 fours and two huge sixes.
Earlier in the day, Vale had delivered a strong all-round bowling display to limit Watford Town to below 200.
Steven Allweis (1-33) produced what is quickly becoming his trademark, grabbing a wicket in the first over of the innings to get Vale off to a flyer.
The Reingold brothers, Steven (1-24) and Grant (1-31), bowled with great control, never allowing the home side's batsmen off the leash - and Benjamin Lederman then picked up the rewards.
He took 6-32 to dismantle the Watford Town batting line-up, who were unable to cope with his array of non-spinning deliveries.
Lederman's haul and a much-improved fielding effort from LMV restrained the home side to a well under-par total - and despite an early wobble, cool heads from Kohler and Spooner saw Vale home, and made it two wins from two in the league this season.
Steven Allweis 8-1-33-1
Steven Reingold 7-1-24-1
Rafi Saville 4-0-25-0
Benjmain Lederman 9.1-0-32-6
Grant Reingold 7-0-31-1
Jonti Aremband 2-0-29-1
Steven Reingold Bowled 0
Alex Haffner Caught 5
Grant Reingold Caught 26
Benjmain Lederman Bowled 11
Ben Kohler not out 78
Adam Spooner not out 56
Did not bat: Jon Galloway, Neil Lederman, Rafi Saville, Steven Allweis, Jonti Aremband