Cultured Roses

Breeding Roses

• Hobbyists and scientists alike work to achieve the next commercial success. Breeders begin with an idea of the qualities and characteristics they wish to develop in a new rose. The interaction of the chosen parents' DNA does not always produce predictable results. Breeders attempt up to thousands of crosses before discovering a potentially successful seedling. The plant is then subject to several years of field trials; breeders discard inferior progeny.

Asexual Reproduction

• Growers cultivate desirable rosebushes through asexual reproduction. Cultured canes and rooted stem cuttings are clones of individual plants. Home gardeners and rose vendors pot rooted cuttings. Canes of chosen cultivars grafted onto selected roots become commercial nursery stock. A genetic mutation or "sport," desirable in form, color or fragrance, is a potential new cultivar with most characteristics of the parent plant. For example, "Chicago Peace" is a widely-grown sport of "Peace."

Tissue Culture

• Horticulturists hope to achieve the rapid multiplication of improved cultivars through tissue culture. Micropropagation offers such advantages as reducing the time from breeding to market, year-round production and disease-free plants. Scientists at Thailand's Prince of Songkia University successfully cultured rose "Perfume Delight" with pieces taken from stem nodes. The scientists cultured sterilized bits of tissue as small as under 1/2 inch in specially prepared liquid shoot-multiplication formulas. Researchers refreshed the medium regularly. Shoots developed and even bloomed in vitro; that is, before potting.

Home Rose Culture

• Home gardeners successfully culture roses in every temperate-zone climate region. Cultivars suited to local conditions perform best. Gardeners should provide at least six hours or more of daily sun exposure, with dappled afternoon shade in the hottest areas. Climbing, shrub, floribunda and miniature roses have varying growth habits and sizes at maturity. Roses prefer slightly acidic soil. Large planting holes and organically enriched soil offer roses a healthy start. Home gardeners should Irrigate with a minimum of 1 inch of water weekly and fertilize roses regularly throughout the flowering season. Air circulation is important around mature plants.