Prince Harry and Meghan Markle have chosen white garden roses, peonies and foxgloves for their wedding day.
London-based florist Philippa Craddock will create the floral displays for St George's Chapel and St George's Hall on 19 May, Kensington Palace said.
Locally sourced foliage will be used, including from the gardens of the Crown Estate and Windsor Great Park.
Ms Markle said on her now-deleted Instagram account that peonies make her "endlessly happy".
Soon after the couple started dating, Ms Markle posted a picture of a bouquet of pink and white peonies on Instagram.
She captioned the picture: "Swooning over these. #London #peonies #spoiledrotten".
Ms Markle revealed in 2014 that her mother, Doria, had always called her "Flower", adding that it was her nickname "since I was a little girl".
Ms Craddock, a self-taught florist, will direct a team from St George's Chapel and Buckingham Palace to create the displays.
The couple's lemon and elderflower wedding cake will also be decorated with fresh spring blooms.