Reducing Pacific Island Growers' Reliance on Off-island Fertilizer Sources Through Improved Awareness and Efficient Use of Local

Project Overview

Project Type: Research and Education
Funds awarded in 2011: $284,070.00
Projected End Date: 12/31/2015
Region: Western
State: Hawaii
Principal Investigator:
Dr. Theodore Radovich
University of Hawaii, Manoa

Annual Reports


Not commodity specific


  • Crop Production: municipal wastes, nutrient cycling, organic fertilizers, application rate management, tissue analysis
  • Education and Training: decision support system, extension, farmer to farmer, on-farm/ranch research, workshop
  • Farm Business Management: budgets/cost and returns
  • Production Systems: transitioning to organic, holistic management, organic agriculture
  • Soil Management: organic matter, soil analysis, nutrient mineralization

    Proposal abstract:

    Replacing imported fertilizers with local resources is the highest research, education and development priority identified by the participants of the Western SARE Hawai’i Subregional conference held in Kona, Hawaii (see

    As commercial fertilizer costs increase with oil prices, a wide range of food producers in the Pacific region have become interested in locally available by-products that are suitable for use as agricultural inputs to improve crop health and productivity. These inputs include:

    1) commercial green-waste composts,
    2) rendered animal products (Tankage), and
    3) invasive algae from coral reef remediation projects.

    Although readily available, there are several bottlenecks preventing effective use and adoption by local growers. These include:

    1) commercial composts vary significantly in quality, often have low nitrogen content and frequently very high C:N ratio,

    2) rendered meat product quality also varies depending on feedstock source, and we have yet to fully understand its effects on plant growth under different Hawaiian soils and microclimates,

    3) invasive algae is available in large quantity and can be an important source of K and other plant nutrients, but nutrient content depends on species, and potential salinity concerns need to be addressed.

    As a result, producers are unaware of resources available to them and unsure of their ability to profitably utilize the local resources they are aware of. This problem will be addressed via a series of greenhouse and on-farm trials in cooperation with university faculty, commercial growers and industry partners. At the successful completion of this project, producer awareness of local materials will be increased, and producers will effectively utilize greater amounts these resources in their operations. Consequently, reliance on imported inputs will be reduced, grower profitability increased in the near-term and the long-term stability of Pacific island foods systems improved.

    Project objectives from proposal:

    1. Enhance the capacity of at least 300 growers, compost producers and other agricultural professionals in Hawaii, American Samoa and elsewhere to evaluate compost quality.

    2. Identify the most important variables influencing the effect of rendered meat products (tankage) on plant growth and mineral nutrition in Hawaii and American Samoa.

    3. Quantify the independent and interactive effect of species, collection location and simple processing on nutrient content and availability of three algae species collected from multiple sites on Oahu, Molokai and Hawaii islands.

    4. Ensure dissemination of information from this project to producers and agricultural professionals throughout the Pacific region beyond the project duration.

    Note: Cost analysis of inputs and practices will be conducted throughout all activities.

    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.