Adapting Cut Flower Production for Utah’s Climate and Soils

Steve Elliott

Sustainable Agriculture Fact Sheet                              July 2020

State: Utah                                                                                                                        

Commodity: Cut Flowers

Need: Science-based fertilizer and production recommendations for a new and growing industry

Summary: Growing cut flowers as a high-value crop has recently become popular across Utah because of the crop’s unmatched profitability and small space requirements, yet minimal research and cultivation information exist for Utah.

Background: Because cut flowers are a relatively new crop for Utah, growers use resources and guides that were developed in other states and not appropriate for Utah soils or climate. Over-application of fertilizer and use of unsuitable soil amendments have introduced soil health, long-term productivity and environmental sustainability risks.

The Research: Led by Dr. Melanie Stock, an urban and small farms specialist at Utah State University, the project team set out to to answer several questions by testing a premium cut flower, Dahlia ‘Café au Lait’:

1. What were current management practices and market prices for cut flowers in Utah?

2 What nitrogen rates are needed to maximize economic return on yields (stem length, bloom diameter, and total number of blooms per plant) without buildup of nutrients and salts that negatively affect soil heath, productivity and environmental sustainability?

3. How do native soil conditions and climate impact nutrient management and subsequent yields?

This project established Dahlia trials to test and develop Utah-specific nutrient management plans. Participatory research was conducted with growers to document present management practices, subsequent soil test results, yield, and profitability data on a range of soil types and climates in the state. Multiple Extension education outreach activities were organized through conference presentations, field days, farm tours, and a grower association. The ultimate goal was to create Utah-specific resources for cut flower cultivation that highlight soil health and helps growers increase their efficiency, yields and environmental sustainability. During the research, a viral outbreak occurred at the Utah State research facility, and was quickly discovered to be a problem statewide, identifying a new challenge for growers.

The Impact: This project is improving production efficiency, soil health and the economical sustainability of Utah’s cut flower industry. This study developed soil nutrient recommendations for dahlia and provided growers with a firsthand experience regarding sustainable nutrient management – specifically the importance of soil testing and only adding nutrients indicated by the test. This project also developed optimum nitrogen rates to increase flower yield. The unexpected impact of the study was to expose devastating disease issues for Utah dahlias, which led to a  new collaboration with USU Plant Pathologist Dr. Claudia Nischwitz, who now includes cut flower diseases in her program emphasis. Through work and funding with Dr. Nischwitz, we conducted a state survey of dahlia diseases and determined dahlias at every surveyed farm had at least one viral disease, and some up to three. Utah State University now offers testing to growers and other dahlia enthusiasts, and with new funding is developing tools to identify virus presence, expanding soil testing (some viruses are affected by soil nutrient ratios), and increasing consultations and social media presence to address the challenges of growing dahlias.

Project report

Utah Cut Flower Farm Association

More information: melanie.stock@usu.edu, 435-797-0248