Rose growers are always looking to create roses with better characteristics. Some growers prefer roses with larger blossoms, longer stems, more vivid color, or that are more disease resistant. To obtain these new and better roses, two roses must be crossed (hybridized). In nature, this crossing is done by bees or other insects capable of carrying pollen. Rose hybridizers desire more control on the parents of the new rose than can be obtained by natural pollination.
Hybridizers collect the pollen from one desirable rose (pollen parent) and apply the pollen to the blossom of another desirable rose (seed parent). After the seed parent is fertilized, the area underneath the blossom will swell and form seeds. Typically between 90 and 120 days after fertilization, the seeds will reach maturity and can be extracted. After chilling the seeds for a period of time, they then can be planted. Rose seeds can be slow to sprout and it is not uncommon for seeds to be in the soil from three to eighteen months before the new rose plant starts to grow.
After the seed sprouts the first blossom may develop in six weeks. An extensive evaluation period is usually required before all the roses' characteristics can be determined. If a rose has desirable features it may take five to seven years before a new rose can be mass produced and marketed.