The rainbow rose is a rose which has had its petals artificially coloured.
The colouring method exploits the rose's natural processes by which water is drawn up the stem. By splitting the stem and dipping each part in a differently coloured water, the colours are drawn into the petals resulting in a multicoloured rose.
The rainbow rose has been developed by a collaboration of two dutch companies, River Flowers and F.J. Zandbergen & Zn. Together they formed Happy Roses to produce and market rainbow roses.
River Flowers started as a cultivator of chrysanthemums. In 2004, they developed a method of adding colour to the petals of chrysanthemums and applied for a worldwide patent.
Zandbergen is a large company which specialises in everything to do with roses. When they happened to come into contact with River Flowers in 2006, the colouring process was tried on roses and found to be successful.