STEMS Flower Market will be on show to the nation on Friday, with their flower arrangements taking centre stage at Telstra Dome.The Ballarat flower market has been chosen by the Catholic Diocese of Melbourne to prepare and supply flowers for their commencement mass this weekend, as part of World Youth Day.Up to 50,000 people are expected to attend the ceremony.Yesterday, the staff at Stems were busy with their floral creations, which will be delivered to Telstra Dome tomorrow.Stems' assistants Marjorie O'Donnell and Pam van Every had been working on the arrangements since 8am, and were expecting to work throughout the day to finish a 10-foot long bench display. "We've got to make sure the buds will flower at the right time, and by Friday night, they will be in full bloom," Ms van Every said.