Traditionally, a yellow rose stands for friendship, according to Morrison Gardens. Yellow roses are commonly sent when the occasion calls for roses but not romance, such as sympathy messages or to thank a co-worker.
Yellow roses are a relatively new entrant to the commercial rose world. They were discovered in Asia by European rose enthusiasts during the 18th century. After years of hybridization, today's yellow rose only slightly resembles its wild ancestor. Fuller, larger blooms with strong rose fragrance are typical of the modern form. White, pink and red roses had been assigned specific meanings in the Middle Ages; the yellow rose was assigned its own special set of meanings during the Victorian era.