Authors:

Blaine Hanson
UC Irrigation and Drainage Specialist, Department of Land, Air, and Water Resources, UC Davis


Neil O'Connell
Farm Advisor, Tulare County, UCCE


Jan Hopmans
Professor, Department of Land, Air, and Water Resources, UC Davis


Jirka Simunek
Professor, Department of Environmental Sciences,
UC Riverside


Robert Beede
Farm Advisor, Kings County, UCCE

2006, 49 pp - Publication# 21620- $25
Last revised: Fall 2006

If you have comments or suggestions, please email the LAWR webmaster at lawrweb@ucdavis.edu

Last updated February 2, 2007

    Fertigation and Microirrigation
    Publication #21620


    Table of Contents

    List of Tables

    List of Figures

    Introduction

    Characteristics of Selected Fertilizers Commonly Used for Fertigation

  • Units of Concentration
    •
  • Characteristics of Fertilizers
  • Fertilizers Commonly Used with Microirrigation
  • Considerations and Constraints

    • Where does the Nitrogen Go?

  • Forms of Nitrogen
  • How Nitrogen is Taken Up
  • Leaching

    • Fertigation Strategies

  • Considerations
  • Long-duration and Short-duration Fertigation
  • Which is the best Strategy?

    • Applying the Right Amount of Fertilizer

  • Calculating the Injection Rate or Injection Duration

    • Nitrogen Irrigation in Water
  • Crop Response to Leaching Fraction and Salt Distribution

    • Frequency of Fertigation

    Applying Fertilizers Uniformly with Microirrigation
  • Fieldwide Uniformity
  • Localized Uniformity

    • Nitrogen Fertilizer Distribution Around Drip Lines

  • Nitrate Distribution
  • Effect of Fertigation Strategy on Nitrate Distribution
  • Urea Distribution
  • Ammonium Distribution
  • Conclusions
    •

    Phosporus and Potassium Fertilizer Distribution Around Drip Lines

  • Phosphorus
  • Potassium

    • Injecting Gypsum

  • Reasons for Injecting Gypsum
  • Water Quality Effects
  • Calculating Gypsum Amounts
  • Considerations in in Injecting Gypsum

    • Mixing Considerations

  • Fertilizer-Water Reactions
  • Mixing Fertilizers
    •

    Injection Devices

  • Batch Tanks
  • Venturi Injectors
  • Positive Displacement Pumps
    •

    Preventing Backflow

  • Backflow Prevention Devices
    •

    Safety Concerns

    Please direct any comments or questions about the material contained herein to Blaine Hanson (email: brhanson@ucdavis.edu), Department of Land, Air and Water Resources, University of California, Davis, CA 95616, telephone number: (530) 752-1130; fax number: (530) 752-1552.