Comparing Organic and Conventional Fertilization Methods for Cut Flower Production in Haygrove High Tunnels

Project Overview

Project Type: Graduate Student
Funds awarded in 2004: $10,000.00
Projected End Date: 12/31/2006
Grant Recipient: Kansas State University
Region: North Central
State: Kansas
Graduate Student:
Faculty Advisor:
Kimberly Williams
Kansas State University

Annual Reports


  • Additional Plants: ornamentals


  • Crop Production: fertigation, organic fertilizers, tissue analysis
  • Farm Business Management: budgets/cost and returns
  • Production Systems: general crop production
  • Soil Management: nutrient mineralization


    Rates of organic and conventional slow release and soluble fertilizers were evaluated for lisianthus, which was found to have moderate fertility requirement: 1.8 to 3.6 kg per cubic meter conventional slow release fertilizer (Nutricote 20-3-8.3) and soluble fertilizers of organic Daniel’s (10-1.7-2.5) and conventional salt-formulated fertilizer at 75 to 150 ppm nitrogen produced optimal yield.

    Light, air temperature, fertilization, and humidity were evaluated to optimize germination of the cut flower ‘Temptress’ poppy, which promises lucrative economic returns for market farmers. Optimal growth was obtained with cool air temperatures of 18 C, elevated humidity, and light fertilization with 25 ppm nitrogen.


    Organic cropping practices are not limited to farms producing foodstuffs. Many ornamental crop and specialty cut flower producers also seek to adopt sustainable production practices. However, little information is available concerning the use of organically-certifiable fertilizers for cut flower production. Lisianthus (Eustoma grandiflorum) is a very popular cut flower for production by market farmers and represents a model species to study organic versus conventional fertilization practices for cut flower cropping systems.

    Since its release, giant Oriental poppy (Papaver orientale ‘Temptress’) has rapidly gained popularity among specialty cut flower producers due to its large flowers, which can reach 9 cm in diameter. Very few guidelines that cite optimal environmental conditions for germination and seedling development of Oriental poppy are available, and what is published is in conflict. Cut flower growers have expressed frustration with germination of the expensive seed for this crop.

    Project objectives:

    The original goal of this research project was to generate practical information about the use of organic compared to inorganic fertilization for cut flowers produced in Haygrove high tunnels. During June and July 2004, an experiment was conducted in the Haygrove tunnels at the Eastern Kansas Horticulture Research and Extension Center in Olathe, Kansas, to compare organic versus conventional fertilizers at three rates of application for sunflower production in Haygrove tunnels. However, the soil was already so fertile that no treatment differences were observed in this preliminary experiment (see 2005 Annual Report).

    Unfortunately, all high tunnels at the Eastern Kansas Horticulture Research and Extension Center were destroyed by a microburst in August 2004 (see for photos of damage.) Four experiments associated with this project were planted in the Haygrove high tunnels at the time of the microburst and were destroyed (organic versus conventional fertilization studies for cut sunflower, lisianthus, ornamental kale, and ‘Temptress’ poppy). Reconstruction of the high tunnels occurred over the next 1.5 years, which made their use in the project of this report unfeasible, though we now have a working knowledge of the management issues associated with Haygrove high tunnels to pass along to farmers.

    The research site was moved to the greenhouses of Kansas State University’s main campus in Manhattan, Kansas, where organic versus conventional fertilization of the cut flower lisianthus was studied. In addition, the objective of determining optimal environmental conditions for germination and seedling development of ‘Temptress’ poppy was added to the project. The final objective of the project is to share the information generated with cut flower growers and market farmers via and the Association of Specialty Cut Flower Growers’ (ASCFG) Cut Flower Quarterly.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.