Think of a funeral and you think of flowers. What roles are they playing there? First of all, they provide comfort. Flowers are calm, beautiful and dignified. They are pleasantly scented, so they don't remind us of the ugly side of death. Because they are plants, they don't have feelings and they don't suffer the way people and animals can. But they're not cold and lifeless like stone: they're alive in their own quiet and unthreatening way. They offer a point of focus for the grieving mind - a reassurance that the world is not the ugly, cruel and meaningless place that it can seem when we experience a death. In other contexts, flowers can be cheerful. In the context of a funeral, they are consoling.
It's also important that flowers do not last for ever. They grow from seed, bloom and flourish, then wither and fade. They are symbols of human life in all its stages, from birth to death, but we display them at their fullest and most beautiful, to remind ourselves of the life that has passed and to celebrate the good things that it contained. We know that, unlike a tombstone or memorial, the flowers at a funeral are not permanent. They will pass like the individual whose burial we are attending.
In this way, they are like companions for the departed. First they represent life at its full, then the fading and end of that life. It's almost as though they follow the departed into the afterlife. We know, too, that flowers grow from something that can seem ugly and unattractive: cold and dirty soil. Death and decay are a necessary part of the cycle of life. The beauty of a rose or lily springs from something that seems dark and lifeless.
In this way, flowers symbolise possibility of renewal, both of our own lives after the passing of grief and of our good memories of the departed person. We know that we can return to the grave to commemorate the departed with fresh flowers. That is part of the ritual of grieving. Flowers are a reminder that grief will fade, but happy memories will remain.