Understanding Leaching Fraction Testing: A Beginner’s Guide
Introduction - What is a Leaching Fraction?
Leaching fraction testing is a crucial best management practice in the container nursery industry, helping optimize irrigation efficiency. This guide will walk you through the steps to perform this test effectively.
Leaching fraction is the amount of water that drains out of a container after irrigation, divided by the amount of irrigation water applied. It helps determine the efficiency of your irrigation system.
The process of taking a leaching fraction measurement is quite easy with a scale, clipboard, and sleeve pot, as the image on the right depicts. See more details below with specific steps to take.
Steps for Conducting a Leaching Fraction Test
1. Preparation:
Select 3-5 random plants from your overhead or sprinkler-irrigated area.
Just before their scheduled irrigation, weigh each plant and its container.
2. Initial Weighing:
Place each plant in an identical, empty container without holes.
Record the weight of each plant and container.
3. Irrigation:
Return the plants to their positions and irrigate as usual.
After irrigation, weigh and record the plants again.
4. Collecting Leachate:
Allow the excess water (leachate) to drain into the containers without holes.
Weigh and record the containers with leachate.
5. Calculations:
Subtract the initial container weight from the post-irrigation weight to find the amount of leachate.
Calculate the leaching fraction:
Best Practices
Aim for a leaching fraction of 10-15%.
Adjust irrigation based on the results: increase if the fraction is low, and decrease if it’s high.
Conclusion
Regular leaching fraction testing can significantly enhance your irrigation practices, leading to better water management and healthier plants. Conduct these tests periodically and adjust your irrigation schedules accordingly to maintain optimal plant growth and resource use.
Special Thanks
Thanks to the contributors to this post including Tom Yeager and Jeff Million.
Sources:
Million and Yeager 2024. Jeff Million and Tom Yeager, UF IFAS Extension Publication #ENH1268 May 21, 2024. Monitoring Leaching Fraction for Irrigation Scheduling in Container Nurseries. https://edis.ifas.ufl.edu/publication/EP529
