Fertigation with Microirrigation


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 BeedeFarm 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


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.