Trees of Remembrance are now standing at its branches Douch & Small in Wimborne, AE Jolliffe & Son in Ferndown, Lesley Shand in Corfe Mullen and Blandford, Ives and Shand in Parkstone and Albert Marsh in Wareham and Upton.
Anyone from the community is invited to pop in to a branch and write a message for a loved one then hang it from the tree.
It is anticipated that by Christmas the trees will be dripping with moving messages.
While it is free to put a message on a tree, for a small fee a bauble can be purchased to hang on a branch and monies collected will go to Dorset Mind.
The group’s James Smith branch in Swanage has sponsored Christmas trees at Emmanuel Baptist Church in Swanage and St George’s Church in Langton Matravers, upon which messages can be left.
Charlie Loveday, from the Upton branch, said: “It is a wonderful tradition and this is this is the fourth year we’ve done it at our branches.
“People really do find it helpful to write a message to a loved one – it doesn’t matter how long ago they passed away.
“We’ve contacted all the people we’ve looked after this year and sent them specifically-designed cards that are available in our branches.
“We’re inviting anyone in the community to get involved.
“For many it will be the first Christmas without a wife, husband, mother or father and the words are very moving.
“A tree of remembrance is a wonderful way to capture special memories and to celebrate a life.
“We invite anyone to come and hang a message from the trees. Any donations will go to Dorset Mind.”