Advancing sustainable nitrogen management in strawberries through participatory research and education

Project Overview

Project Type: Professional + Producer
Funds awarded in 2017: $49,937.00
Projected End Date: 10/31/2020
Grant Recipient: Resource Conservation District
Region: Western
State: California
Principal Investigator:
Sacha Lozano
Resource Conservation District of Santa Cruz County


  • Fruits: berries (strawberries)


  • Crop Production: application rate management, fertigation, fertilizers, nutrient management
  • Education and Training: decision support system, extension, farmer to farmer


    The use of pre-plant controlled release fertilizers (CRF) -regardless of pre-plant soil nitrogen levels- has been a common practice for years among strawberry producers on the central coast. UCCE research has questioned the efficiency and the value of CRF use, by showing that CRF releases nitrogen at a faster rate than crop uptake (leading to nitrate loss) and that reducing pre-plant CRF application by 50% or more has no effect on fruit yield. This project engages partnering professionals and strawberry producers in a collaborative research and education effort seeking to build confidence in research findings, and increase adoption of more sustainable nitrogen fertilizer use practices reflecting current knowledge and understanding. The project addresses the question:  If growers reduce Controlled Release Fertilizer application by 50% or more and instead use data driven fertigation practices is yield maintained? Project Partners will address this question  in multiple production settings and varying acreages to: a) design and implement field trials to evaluate different levels of CRF application in commercial fields, and b) interpret and disseminate the results to other growers and professionals. The experience of collaboratively designing and implementing research trials will not only produce new knowledge, but it will help growers gain confidence and ownership of the scientific research process, while helping researchers better understand barriers to adoption of new management practices. 

    Project objectives:

    By the end of the two and a half year project period we expect to meet the following objectives:

    1. Improve understanding among partnering professionals and producers about the effectiveness and limitations of different levels of controlled release fertilizer (CRF) application on commercial strawberry fields on the California Central Coast, considering their associated impacts in terms of crop yield and potential water quality impairment.
    2. Through participatory field trials with 5 strawberry growers, improve producer confidence in research results and recommendations, as well as their own capacity to evaluate and communicate the effectiveness of nitrogen management practices.
    3. Through participatory education and outreach to 30-50 additional strawberry growers on the Central Coast, increase willingness to reduce CRF applications and try more efficient, data-driven nitrogen management practices on a test plot within their own operations.
    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.