The prize for the popular riverside parkland is one of only 72 issued nationwide for the well managed eco-sites managed by voluntary and community groups.
The latest prize has delighted the leader of the green management team's Ron Freeland, particularly as it falls in the run-up to the judging of Garstang's entry in the Entente Florale contest.
Mr Freeland said: "To win this award for four consecutive years is a major achievement and is thanks very much to the management team.
"We are helped by the Wyre rangers who provide not only labour but expertise."
The award will be presented to Mr Freeland and his colleague Brian Taylor at a ceremony in Liverpool tomorrow (July 24).
Green volunteers are currently preparing the area for both the North West in Bloom contest and next month's visit of the Entente Florale judges.
This year's improvements to the Green include new perennial flower beds.
The next venture planned at the Green is a picnic area for families and school children.
* For information on all winners please visit: www.greenflagaward.org.uk