Members of Urban Saints will be performing a flashmob - a form of synchronised movement - in Trafalgar Square before handing out the flowers wearing red hoodies.
The roses have a link to a website, where people can find out about God's love for them as individuals.
Young people wearing hoodies are sometimes associated with crime, and Urban Saints hopes to go against this stereotype.
Phil Hulks, from the organisation, told Premier Drive: "The roses have a little message on them which basically says 'do you know that you are completely and absolutely loved? How will you pass the love on?'
"And then it will point them to a website... to actually find out more information on who it is that actually loves them.
"Most people today have this image that God is distant, he's disapproving, that he's not interested in them, whereas we're clearly wanting to tell them that God is actually a loving Father who longs to have a relationship with us."
"It's [the hoodie] become a symbol of young people doing bad things, and therefore the Saints in the City are wearing red hoodies and actually going out onto the street and doing good things, and to begin to reclaim back the hoodie as a symbol of love and peace on the streets."
Listen to Premier's Loretta Andrews speaking to Phil Hulks on Drive:
