The University of Arizona: Mastering Irrigation in the Desert
August 27 @ 6:15 pm - 8:15 pm
$20
If you’ve ever heard, “I water every day for 30 minutes because that’s what the controller is set on,” this session is for you. Desert irrigation doesn’t have to be guesswork – and it certainly doesn’t have to waste water. Join Donna DiFrancesco, horticulturist and Conservation Coordinator for the City of Mesa, as she introduces the newly updated Landscape Watering by the Numbers guide and breaks down the art and science behind efficient watering in Arizona’s desert climate.
We’ll go beyond rules of thumb and explore how plant type, soil type, emitter flow rates, and seasonal demand all work together to determine proper run times and watering frequency. Through real-world examples and practical calculations, you’ll see how small adjustments can lead to deeper roots, healthier plants, and more resilient landscapes. Whether you’re advising homeowners, teaching classes, or fine-tuning your own landscape, you’ll leave with updated tools and a clearer framework for watering deeply, infrequently, and seasonally with confidence.
Learning Objectives
By the end of this session, participants will be able to:
• Explain the relationship between plant type, soil type, and irrigation frequency.
• Calculate irrigation run time using emitter flow rates and plant water needs.
• Identify common watering mistakes and recommend corrective strategies.
• Adjust irrigation schedules seasonally to improve plant health and water efficiency.
• Communicate “watering by the numbers” principles clearly to homeowners and clients.
Bio:
Donna DiFrancesco is a Horticulturist and Conservation Coordinator with the City of Mesa Environmental & Sustainability Department where she educates Mesa residents and businesses about Xeriscape, water conservation, living green, and sustainability. Prior to taking her position at the City in 1997, she worked as a Horticulture Program Coordinator for the University of Arizona Maricopa County Cooperative Extension Office and as a Revegetation Ecologist (overseeing maintenance of arid landscapes) for the Flood Control District of Maricopa County. She has an associate’s degree from the University of New Hampshire in Plant Science and a bachelor’s degree from the University of Missouri-Columbia in Horticulture.