Starting on 29 July the 11 judging teams will be assessing more than 5,000 acres of public green space in 72 locations that have planted their way to the UK finals of Bloom, Europe's biggest community gardening campaign.
Each finalist will be awarded a Gold, Silver-Gilt, Silver or Bronze medal. There is also an award for best in category, as well as special discretionary awards given for achieving excellence in particular fields. Results will be announced on 14 October.
This year Birmingham (Heart of England), Cleethorpes (East Midlands), Durham (Northumbria), Lytham (North West) and St Pierre du Bois in Guernsey will be competing for the title of Champion of Champions, the ultimate Britain in Bloom award.
To be considered for the top Bloom awards the judges take into consideration three key criteria: horticultural achievement, community participation and environmental responsibility, demonstrated across public spaces, such as town or city centres, parks and communal gardens, as well as natural spaces including conservation areas and wildflower meadows.
Complementary factors, such as the condition of street furniture and the involvement of young people in Bloom activities, will also count in the assessment of groups.
In preparation for the judging, thousands of Bloom volunteers have been working to transform derelict land into community gardens, brighten streets with floral displays, litter-pick, grow healthy produce, and so much more.
RHS research has revealed the scale of the work undertaken by groups who have planted more than 10m trees, bulbs and other plants over the past year, and donated 11.7m hours of their time for free in order to improve their communities.
Judging panel chair Roger Burnett said: "Britain in Bloom is a real movement for good that is transforming neighbourhoods, creating communities and bringing the many health and wellbeing benefits of gardening to increasing numbers of people from every walk of life.
"The RHS Britain in Bloom finals is an opportunity to celebrate the tens of thousands of often unheralded volunteers who readily give up their time to improve their local environment. My fellow judges and I are immensely proud to be able to see the fruits of their labour and celebrate the work they do."
Andrea Van Sittart, RHS head of regional development, said: "RHS Britain in Bloom puts community achievement front and centre, as we recognise the amazing work have done, often under incredibly difficult circumstances.
"This year we will be presenting a new award that will recognise the efforts Bloom groups have made to make their communities greener and more beautiful places, often while facing adversity - from flooding to extreme heat and vandalism.
"Although the character, selflessness and resolve of Bloom Groups are well known, this new award will shine a light on the often uncelebrated work communities do to make the UK a greener, healthier place to live."
"The finalists should be immensely proud of all they've achieved to get this far, and I wish them the very best of luck.'