Note: This is part of a Research Update series that highlights projects funded by the California Department of Food and Agriculture (CDFA) Fertilizer Research and Education Program (FREP) annual grant program.
Project Title: Promoting the adoption of CropManage to optimize nitrogen and irrigation use through technical assistance with data loggers and cellular modems for Spanish-speaking growers in Santa Cruz and Monterey Counties
Project Leader: Sacha Lozano, Program Manager, Resource Conservation District (RCD) of Santa Cruz County
Project location: Santa Cruz County
Project Status: Complete
Overview
The main objective of this FREP-funded project was to increase understanding of weather-based irrigation scheduling support tools and nitrogen (N) best management practices among Spanish-speaking growers by increasing adoption of CropManage and assessing its effectiveness and impact.
Highlights
- This project contributed to capacity building and broader adoption of CropManage among historically disadvantaged growers
- The outreach, education, and direct technical assistance helped remove some of the existing barriers for adoption of smart and automated tools
- Most of the grower participants using CropManage were able to reduce irrigation water in their fields
- Distrust for new ideas, lack of time for learning new knowledge, and hesitation to revise persistent cultural practices remain some of the main barriers to adoption
- Developing confidence and capacity for adopting decision and management support tools can be a slow process, particularly among disadvantaged growers
Background
Irrigation and N management are critical and challenging components of specialty berry and vegetable crop production on the Central Coast due to increasing regulations and production costs in California. Inadequate management of these resources can result in either an excessive or insufficient supply of water and N to crops, which can impact production and the environment.
CropManage is a powerful and relatively easy-to-use decision-support tool that can help growers with their irrigation scheduling and N application planning. The goal of this project was to facilitate the understanding and adoption of management and decision-support tools such as CropManage and improve irrigation scheduling and N management among Spanish-speaking berry and vegetable producers.
Approach
Using commercially available flowmeters, data loggers and modems, the project team assisted 20 Spanish-speaking growers over two years (2021-2022) to monitor irrigation water use, measure changes in soil moisture and soil N levels, and keep track of concurrent weather-based crop demand (Fig. 1). This information was entered into CropManageto generate management recommendations, keep records of applied water and N, and compare applied vs. recommended amounts.
Participating growers received individual assistance, training, and periodic feedback during the growing season to assess and adjust their irrigation and N fertilizer scheduling to minimize over- or underapplication. Growers received simple graphs comparing their cumulative water use to CropManage’s cumulative irrigation recommendation.
The project also provided education and outreach through training and technical assistance in the field, trainings in Spanish for groups of irrigators and ranch managers, and hands-on classroom trainings on the use of CropManage (Fig. 2 and 3).
Figure 1. Flowmeter and solar powered telemetry stations (datalogger + modem) installed on selected planting blocks along sub-main irrigation lines.
Figure 2. Field technician demonstrating how to enter and access information in CropManage using a mobile phone in the field.
Figure 3. RCD staff training growers on the use of the soil nitrate quick test to guide N fertilizer application using CropManage.
Project outcomes and impact:
This project promoted the adoption of CropManage for improved irrigation and N management practices among historically disadvantaged growers. Implementing decision support tools, like CropManage, can be daunting to growers due to the perceived technical requirements and overall lack of confidence in the resulting recommendations. The project team demonstrated that 1:1 technical assistance and continual support are essential for fostering trust and building a grower’s capacity to adopt and get the most out of these management tools and recommendations.
In year one of the project, monitoring data indicated that most participants applied more water than was recommended based on weather and crop demand. While in year two, the cumulative amount of water applied closely matched the recommended amount for most participants. Most grower participants who showed overirrigation trends at some point during their crop cycles stated that they were able to adjust their irrigation scheduling (reduce water applied) based on the periodic reports, and this shift was evidenced in cumulative applied vs. recommended charts. This shift suggests an increased confidence and ability to use the monitoring tools and concepts provided by the project team and CropManage recommendations.
Based on the end-of-season surveys some grower participants expressed and demonstrated the confidence in autonomously using CropManage and monitoring tools to guide their irrigation and nitrogen management practices. However, most grower participants indicated a preference for continued technical assistance and support to fully adopt the tools. This project reaffirmed that the deployment, retrieval, and management of flowmeter and data logger units in the field still requires external assistance by an agency or a third party. In addition, for effective use of decision support tools such as CropManage, irrigators and ranch managers must invest time to familiarize with and develop trust in them. Lessons learned from this project have the potential to help technical service providers promote and facilitate the adoption of irrigation and nitrogen management tools and practices.