Ornamental Research
Plant Trials
Garden Debut® is a Superior Landscape Collection made up of Great New Plants™ and Trusted Selections™ that have been thoroughly tested for long-term performance through Greenleaf Nursery. The Proven Winners™ brand was founded in 1992 with the goal of introducing the best, most unique, high performing plants, to produce them under the highest quality standards, and to market the plants innovatively. Plants from both trials are available from garden centers or independent retailers throughout North America. Both trials are located at the Botanic Garden at Oklahoma State University in Stillwater, OK. These gardens have areas for the general public to become acquainted with plants that grow well in Oklahoma.
Plant Growth Regulators (PGRs)
Greenhouse grower are constantly trying to control plant quality with the use of chemical plant growth regulators. Most are used for controlling plant height, but some can be used to increase branching, which can save on labor costs while producing a better quality plant. Poinsettias has been a staple for the Christmas holiday for almost a century and are the #2 potted crop in terms of value. Although the genetics have improved, all varieties need to be pinched to encourage lateral bud growth. however, some varieties do not branch consistently to produce a marketable potted crop. Current research is looking at using Attrimmec to increase branching and plant quality in poinsettias.
Colored Shade Netting
Research will evaluate colored shade cloth for cut flower production to compare yield and quality to support local market production. To control heat during the summertime, growers use black shade netting to cool the greenhouse. Knowing that plants respond to specific wavelengths, colored shade netting technology has begun to emerge but is not widely tested in the U.S. despite other countries reporting longer stems, improved yield, and more compact plants depending on the species and shade netting color used. This research will evaluate two different species response to three different colored shade nettings. Data will be collected on plant growth to make a recommendation on the value of adapting an already common method used in production of the crops.
Rose Rosette Disease
Rose Rosette Disease was first reported in the U.S. in 1940 yet still remains a challenging disease to date. While progress continues in combating this fatal disease specific to roses, researchers across the country continue to explore ways to manage the disease while ultimately looking for a “cure”. Determining roses that are resistant to the Emaravirus and/or resistant to the specific eriophyid mite that vectors the disease, will aid breeders in introducing new generation roses that can thrive in the presence of the mite and virus. Because over $50 million in losses, roses and/or jobs, have been realized in the U.S. as a result of this disease, it clearly deserves time and attention from university personnel. Jen Olson, Entomology and Plant Pathology and Mike Schnelle, Horticulture and Landscape Architecture, have had trial plots for over four years now serving as an opportunity to screen roses for potential resistance as well as experimenting with cultural techniques to mitigate the ravages of this disease.
Potted Plant Production is a Billion Dollar Market in the Plant Industry
Growers are looking for ways to increase production quality while decreasing cost and environmental impact. The use of nondestructive, optical sensors has been investigated on twelve different greenhouse crops (including poinsettia, chrysanthemum, marigold, and geranium) to improve nitrogen use efficiency, increase plant quality, develop a sampling protocol, and reduce costs associated with other sampling methods.
Fact Sheet HLA-6719 has been developed to inform growers about optical sensors. Results from the studies have shown that for all but one crop, the atLEAF chlorophyll sensor performed as well as the SPAD chlorophyll meter, which is considered the standard but costs ten times as much as the atLEAF sensor. Location of sensor readings within a leaf and not just location within a plant canopy can affect readings. In addition, a new mobile iPhone app (Plant Nitrogen Recommendations) was developed where someone can input atLEAF, SPAD, or leaf nitrogen lab analysis values into the app for over 150 different ornamental crops. The app then gives a recommendation if additional fertilizer is needed. Current research is looking at how many samples are needed for accurate analysis, what affect other nutrients have on sensor readings, and how timing of fertilizer application can affect sensor readings.