Source: UNIVERSITY OF FLORIDA submitted to
DEVELOPMENT OF A SYSTEM APPROACH TO ORGANIC GREENHOUSE HERB PRODUCTION FOR PROTECTED AGRICULTURE IN A MILD WEATHER CLIMATE
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
Reporting Frequency
Annual
Accession No.
0200810
Grant No.
2004-34135-14800
Cumulative Award Amt.
(N/A)
Proposal No.
2004-05106
Multistate No.
(N/A)
Project Start Date
Sep 15, 2004
Project End Date
Sep 14, 2006
Grant Year
2004
Program Code
[AH]- (N/A)
Recipient Organization
UNIVERSITY OF FLORIDA
G022 MCCARTY HALL
GAINESVILLE,FL 32611
Performing Department
NORTH FLA RESEARCH & EDUCATION CENTER, QUINCY
Non Technical Summary
The demand for organic food crops is increasing every year in the world and farmers are investigating opportunities for taking advantage of the increased demand. The organic food section in most grocery chains in the U.S. is one of the fastest growing sections of the produce sector. Field production of organic herbs is very challenging due to the paucity of information about production techniques and the lack of effective pest management tools. The general purpose of this research project is to establish production recommendations for the successful production of organic herbs in subtropical and tropical Florida and the Caribbean region.
Animal Health Component
100%
Research Effort Categories
Basic
(N/A)
Applied
100%
Developmental
(N/A)
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2052235106040%
2052235113020%
2152235113020%
6012235106010%
6012235113010%
Goals / Objectives
Organic crop production systems have been well established for certain growing areas in the U.S. and the world, especially for mild Mediterranean and desert areas around the world. Organic crop production in humid subtropical and tropic regions is less developed because production practices under these more challenging climates have not been well established. The general objective of this research project is to establish production recommendations for the successful production of organic herbs in subtropical and tropical Florida and the Caribbean region. Herbs of major interest are basil, mint, chives, oregano, marjoram, thyme, rosemary, and cilantro. Specifically, the objectives are to develop fertilization programs, including nutrient sources, fertilization rates, and timing of application for at least three production systems, including perlite-filled trough, nursery container, and small-pot systems for greenhouse-grown organic herbs; to develop integrated Pest Management programs for organically-grown herbs, including selection of appropriate predator or parasite and timing of release in the crop; to evaluate the post-harvest quality of organically-grown herbs; and to compare the profitability of the various production systems.
Project Methods
The research for this project will be conduced at three locations in the state of Florida and the commercial growers have agreed to be cooperators on this project. Organic fertilizers will be mixed with the soilless media at various rates prior to filling pots or troughs. Examples of approved organic fertilizers to be used in this research include Fertrell 4-2-4 from Fertrell, Inc. (Bainbridge, PA)and Nature Safe from Griffin Industries (Cold Spring, KY). Organic fertilizers will be applied in two basic methods, for all treatments, a preplant, media incorporation and an in-season side-dressing or top-dressing. The organic fertilizers will be compared to a hydroponic fertilization system where a nutrient solution will be applied to the plants through spray-stakes at 0, 1, 2, and 3 grams of N per plant per application. Examples of split applications to be employed include weekly, biweekly, and monthly applications of fertilizer materials. These factors will be placed in combination with the fertilizer rate factor above to find, for each herb crop and fertilizer material, the optimum combination. Herbs will be grown in the various production systems and harvested according to commercial practices for a particular herb. For example, for basil grown in the trough system, branches are cut from the plant and bunched for packaging. Weights of fresh herbs will be recorded at each harvest and summed for the season. This project will evaluate IPM techniques in combination which are thought to be the best available information. The major pests of concern are anticipated to be silverleaf whitefly, various aphid species, various leaf-feeding worms, broadmites, thrips, and fungus gnats. The IPM treatments will include pest parasite release, pest predator release, banker plant system, insect screens on the greenhouse, environmental controls in the greenhouse, and approved organic pesticides. Weekly monitoring programs using insect traps, plant inspections, and insect collecting techniques will be used as part of the implementation of the IPM programs. Preliminary work with organic herbs in greenhouses has shown the need for some specific research. Research in this TSTAR project should focus on research trials to evaluate control methods for diptera species. The fly species include fungus gnats, Drosophila sp., and a member of the family Sphaeroceridae. Fungus gnats and shore flies are expected, however, the others are new pest species for Florida greenhouse herb production. Treatments include Bacillus thuringiensis formulations, parasitic nematodes, organically approved pesticides and a no treatment control. Samples of freshly harvested herbs will be collected for evaluations of fresh quality. The quality parameters to be measured include color, turgidity, shelf life, decay, and freedom from leaf defects (spots, dead areas). Records of input costs will be maintained for the research projects. Total production costs for the various organic systems will be calculated, permitting comparisons to published production costs for outdoor field production of herbs.

Progress 10/01/05 to 09/30/06

Outputs
The objectives of study one were to develop a fertilization program for greenhouse grown fresh cut organic basil and spearmint in a perlite filled trough system, and to determine the postharvest quality of fresh herbs. Two separate experiments for basil, cultivar Nufar and a local spearmint strain were conducted inside the same double layer polyethylene covered greenhouse with fan and pad ventilation at the Univ. of Florida NFREC Suwannee Valley near Live Oak, Florida. Four certified organic fertilizer treatments with N, P, K analyses (4.0-0.9-2.5, 4.0-0.9-3.3, 8.0-2.2-4.2, and 8.0-2.2-4.2 plus a sidedress of fish emulsion 5.0-0.9-1.7) were evaluated in comparison to a standard non-organic hydroponic fertilizer treatment (150-50-200 mg NPK per L). Treatments were arranged in a RCB design with six replications. Organic fertilizer materials were applied so each treatment received the same total nitrogen amount. Plots were drip irrigated, except the hydroponic treatments which received water plus nutrients. The organic 4.0-0.9-2.5 fertilizer resulted in greater basil fresh weight yields (488 gram per plant per season) than remaining organic treatments, but less than the standard hydroponic solution (583 gram per plant per season). In spearmint, greatest fresh weight was observed with the hydroponic (597 gram per plant per season), followed by organic 8.0-2.2-4.2 + 5.0-0.9-1.7 (533 gram per plant per season). Two new data sets on petiole, leaf, and plant N and K will be the basis for nutrient recommendations in greenhouse basil and spearmint. Selected evaluations of the postharvest quality of the herbs were made. There were no significant differences in leaf color or moisture content between due to treatment or harvest date. Leaves became duller and slightly less green after 14 days of storage. Leaf moisture content was about 90 percent for harvest 1, and about 88 percent for basil for harvests 2 and 3 and for mint for harvest 2. There were no discernable trends between treatments for firmness data. Decay was present in all treatments except for the pm harvests for basil harvest 1 after 7 days storage. There was no decay for basil test 2 except for treatment 3. For basil test 3 there was no decay on day 7, but on day 14 all treatments except the pm harvests had some decay. Decay was present to some degree in all treatments for mint test. There was no decay on day 7 of mint test 2 and little decay on day 14. Overall, effects of the nutrient regimes, harvest time (morning or afternoon) and harvest date were insignificant relating to the postharvest quality parameters measured during 14 days storage at 12.5C (basil) or at 5C (mint). In study two, coriander and dill herbs were grown in four inch pots to measure fresh container production potential. All measurements except nitrate and total C were significantly affected by fertilizer rates. Coriander grows the best at 4.8 gram N per gal of potting medium. Plants treated with the highest fertilizer rate had the highest concentration of leaf tissue N.

Impacts
Research results from this project will lead to improved herb production efficiency and consistency in organic production systems. Organic herb producers will be able to select fertilizer materials and apply fertilizers more efficiently to the crops. Production efficiency and post harvest quality will be improved.

Publications

  • Hochmuth, R., G. Hochmuth, R. Sprenkel, E. Simonne, D. Treadwell, L. Osborne, T. Olczyk, and Y. Li. 2006. Adopting new plasticulture techniques to grow organic herbs in Florida greenhouses. Proceedings of the 33rd National Agriculture Plastics Congress of the American Society for Plasticulture. (In print) Nov 2-5, 2006. San Antonio, Texas
  • Treadwell, D. D., G. J. Hochmuth, R.C. Hochmuth, E. H. Simonne, S. A. Sargent, L. L. Davis, W. L. Laughlin, Y. Li, T. Olczyk, R. K. Sprenkel, and L. S. Osborne. 2006. Nutrient management for organic greenhouse culinary herbs. (abstract). American Society for Horticultural Science, New Orleans.


Progress 09/15/04 to 09/14/06

Outputs
OUTPUTS: The overall objective of this research project was to determine and demonstrate organic herb production systems for warm-season production in greenhouses. We conducted research at two sites in Florida to determine basic information for producing organic herbs in greenhouses under tropical and semitropical conditions. The two sites were the University of Florida Institute of Food and Agricultural Sciences research and education centers at Live Oak, in northern Florida and Homestead in extreme southern Florida. Regionally important herbs, basil and spearmint were chosen for the research in northern Florida, and dill, basil, and coriander were used in southern Florida. Production system factors, growing media, fertilizer, irrigation, and insect control were evaluated in the research. Research was conducted over a period of three years from 2004-2007 at both sites. At Live Oak, various commercially available organic fertilizer materials were evaluated for basil and spearmint in factorial experiments. Yield of fresh herbs, plant tissue nutrient contents, and postharvest quality parameters of herbs were measured. Post harvest quality parameters included storage life, color, freshness, and weight loss. In Homestead experiments, responses of fresh potted herb yield to fertilizer and irrigation levels were measured. Biological insect controls were implemented in the greenhouses and separate insect control experiments were conducted at a third research and education center in Apopka, Florida. In conjunction with the research experimentation, we carried out field days at the production sites to demonstrate organic herb production systems under development. Presentations by project investigators were made at the field day, discussing results from the research and providing guidelines on organic herb production. Scientific presentations were made at the annual meetings of the American Society for Horticultural Sciences and to the Florida State Horticultural Society. Data developed from the research were analyzed statistically and prepared for publication in peer-reviewed and non-refereed journals. Extension publications were developed for dissemination to county agents and to interested commercial herb growers. Information from the research was used to update the organic crop and hydroponic sections to the small farms website, http://smallfarms.ifas.ufl.edu. PARTICIPANTS: George Hochmuth was Project Director, responsible for coordination of effort, proposal development, research manuscript preparation, and for reports. Robert Hochmuth was project leader for the Live Oak site and for carrying out research and education work, authoring publications, research presentations, farm demonstrations, and updating of small farms website. Danielle Treadwell was responsible for media and fertilizer research at Live Oak and for scientific presentations and journal publications. Eric Simonne was responsible for data analyses and for assisting in publications. Lance Osborne was responsible for aspects of the insect control research. Richard Sprenkel was responsible for the extension education efforts on insect control. Teresa Olczyk provided leadership for the research and extension efforts at Homestead. Kati Migliaccio led the preparation of journal manuscripts on organic fertilization of potted herbs and the extension publications. Yuncong Li led the irrigation research at Homestead and the preparation of manuscripts. Steve Sargent led the research on the post harvest quality of organically grown herbs in the project. TARGET AUDIENCES: The target audiences for this project were in two categories. One audience was the county agents who deal with organic farmers. The project personnel provided training for these agents on organic herb production. The second audience was the commercial organic farmers, who were introduced to organic herb production and who were assisted by project personnel and trained agents. PROJECT MODIFICATIONS: The project was carried out closely to the outline in the project proposals. Minimal modifications were made during the course of the research.

Impacts
Project investigators worked with several organic farmers in both study sites. For example, in northern Florida, two organic farmers followed the project work closely. Project personnel assisted the farmers in adoption of practices developed in the research, including the idea of the trough, based production system, the specific organic media, and the fertilization program. Both organic farmers have increased their organic herb production and attribute some degree of their success to this project. There is a strong interest in organic herb production in Florida and further products from this project, including website information and continued development of educational materials, will be used to assist current and new growers over the next years.

Publications

  • Migliaccio, K., T. Olczyk, Y. Qian, Y. Li, G. Hochmuth, R. Hochmuth, D. Treadwell, E. Simonne, L. Osborne, and R. Sprenkel. Nov. 2006. Fertilizer rates for greenhouse production of container organic fresh herbs in southern Florida. Submitted to HortTechnology.
  • Qian, Y., K. Migliaccio, T. Olczyk, G. Hochmuth, R. Hochmuth, D. Treadwell, E. Simonne, L. Osborne, and R. Sprenkel. Nov. 2006. Irrigation systems for organic greenhouse container herb production. Submitted to HortTechnology.
  • Olczyk, T, Y. Qian, K. W. Migliaccio, Y. C. Li, G. J. Hochmuth, R. C. Hochmuth, E. H. Simonne, D. D. Treadwell, L. S. Osborne, and R. K. Sprenkel. 2007. Nutrient management for greenhouse production of container grown organic herbs. Proc. Fla. State Hort. Soc. V.120.
  • Migliaccio, K. W., T. Olczyk, Y. Qian, G. J. Hochmuth, R. C. Hochmuth, D. D. Treadwell, E. H. Simonne, L. S. Osborne, and R. K. Sprenkel. 2007. Organic greenhouse container herb production in south Florida: Fertilizer and potting media. Fla. Coop. Ext. Serv. Fact Sheet. ABE 373. http://edis.ifas.ufl.edu/AE408.
  • Treadwell, D. D., G. J. Hochmuth, R. C. Hochmuth, E. H. Simonne, S. A. Sargent, L.L. Davis, W. L. Laughlin, T. Olczyk, R. K. Sprenkel, and L. S. Osborne. 2007. Organic greenhouse production of basil and spearmint: Nutrient uptake and postharvest quality. Abstract. HortScience. 42(4): 868.
  • Osborne, L., Z. Landa, G. Hochmuth, R. Hochmuth, R. Sprenkel, and T. Olczyk. 2006. Managing Bemisia on organically grown herbs. Abstract, p128, in Procs. 4th Intl. Workshop on Bemisia.
  • Treadwell, D. D., G. J. Hochmuth, R. C. Hochmuth, E. H. Simonne, L. L. Davis, W. A. Laughlin, Y. Li, T. Olczyk, R. K. Sprenkel, and L. S. Osborne. 2007. Nutrient management in organic greenhouse herb production: Where are we now? HortTechnology 17:461-466.


Progress 10/01/04 to 09/30/05

Outputs
Organic production systems are needed for greenhouse production of herbs. In the first year of research this project investigated the fertilization practices and insect control practices for organic basil and mint production. A greenhouse in Live Oak, FL was used for the research. Five fertilizers were compared for mint and basil, including a control hydroponic treatment and 4 commercial organic fertilizer materials. The herbs were grown in a peat based media and fertilized through the season with split-applications of fertilizers. There were two organic fertilizer treatments that resulted in herb yields comparable with the control treatment. Results from the first year showed that organic herb production is feasible with commercially available organic fertilizers for greehouse culture. Preliminary studies were carried out with insect management in an organically produced herb crop. Silverleaf whiteflies prooved to be the main insect pest. Sampling procedures were tested for fungus gnats.

Impacts
This research will result in the development of protocols for successfully producing organic herbs in a greenhouse. This information with help farmers in tropical areas in the Caribbean region.

Publications

  • No publications reported this period


Progress 10/01/03 to 09/30/04

Outputs
Research with organic production systems for selected herbs was begun on this project in September 2004. The following herbs are being used in fertilization research at the North Florida Research and Education Center-Suwannee Valley: basil, thyme,and spearmint. Four organic fertilizer materials and a hydroponic solution control treatment are being evaluated in the experiments. Treatments have been applied and harvesting was begun on 12 January 2005.

Impacts
This research will result in the developemnt of a fertilization and pest control system for organic herb production in greenhouses in Florida and the Caribbean area.

Publications

  • No publications reported this period