The judges awarded Oldham silver gilt and the top prize at an awards ceremony in St Peter Port, Guernsey on 5 October that was attended by 450 community gardening champions.
To accompany the best city award Oldham also scooped the Pride of Place gong – which recognises the community’s involvement in Bloom and Grow and encompasses Oldham’s ‘Love Where you Live’ Campaign.
Councillor Jean Stretton said: "To participate in such a prestigious event was a real honour and our entry has been warmly welcomed by the whole community in Oldham.
"To win these two categories has added a real sense of achievement and reflects the hard work, dedication and commitment from all who have been involved.
"We are ecstatic with these awards and this is example of Oldham’s growing national reputation as a great place to live, work and visit.
Oldham was chosen as the region’s representative in the 2012 competition, after beating serious rivals Chester and Preston last year to be crowned ‘Best City’ in North West in Bloom.
This year’s entry included the WOW bed in the Town Centre and features such as the Underwater bed on Broadway and the wild flower meadow at Mill Brow.
As well as recognising the physical and environmental improvements Bloom and Grow also involved the community.
McDonald’s restaurants around Oldham carried out litter picks – as part of the Love Where You Live drive – and a wild flower meadow has been worked on by the Gateway Group which supports people who are recovering from drug and alcohol addiction.
The Blooming Banner competition saw more than 700 school children submit a design on the theme of Love Where You Live.
More than 1,200 UK communities, from big cities to small villages, participate in RHS’s Britain in Bloom campaign to green-up and clean-up Britain.
Of these, just 72 finalists were chosen to represent their region/nation in the 2012 UK Finals.