College of Food, Ag & Nat Res Sci
The University of Minnesota Herbaceous Perennial Breeding Program is recognized as one of the premiere public-sector flower breeding project programs in the world. The program's creation of new chrysanthemum plant habits (from large shrubs to groundcover types), discovery and breeding of reflowering, non-vernalization requiring lilies, release of USDA Zone 4 winter-hardy gladiolus, and cold-tolerant gaura are example research efforts enabling the generation of revitalized floricultural crops for the 21st century. For example:
- The new shrub chrysanthemums resulted in increased U.S. chrysanthemum sales from $104.8M (wholesale) in 2001 (when the first shrub type was released) to $123.65M (wholesale) in 2012, helping make mums the #1 herbaceous perennial in U.S. saless. Shrub types also prompted growers to sell traditional cushion cultivars in larger containers to mimic shrub types.
- Winter hardy gladioli would not require digging the corms in the fall for overwintering; multiple flowering stems on each plant would increase cut stem yields.
- Advancements in lily breeding have resulted in the creation of colored, seed-propagated hybrids for continued development and domestication. Lilies, which flower under one year from seed and continuously flower thereafter, will significantly alter production and use of this crop as a cut flower, flowering potted plant, and garden perennial. Cut flower growers could harvest multiple stems/plant (rather than the standard one per bulb) continuously throughout the growing season (field) or in greenhouses (year-round), rather than having to purchase and force a new crop of bulbs for each harvest. Flowering potted lilies would become dual-use products, enjoyed indoors for a holiday and then reflowered either indoors or outdoors for the growing season. As garden perennials, such lilies would allow for flowering throughout the season rather than just for less than one month.
Focus on preventing the creation of invasive ornamental floriculture crops prior to their release onto the market has led to research on contributing factors within the horticultural distribution channel, risk assessment, as well as plant traits to select against during domestication. Reed canarygrass, an ornamental herbaceous perennial, is being used as a model plant in which to study these factors. Continual incorporation of new traits, such as non-invasiveness and drought/heat tolerance will enable continued growth of the floriculture sector with readily adaptable germplasm. Testing for invasive potential of ornamental crops prior to market release must involve genotype-specific testing in multiple sites and locations over years, similar to the methodology used to assess winter hardiness. While costly, the long-term gains in preventing horticultural crop invasions are greater than selling non-winter hardy perennials.