With the availability of irrigation water becoming more and more of a concern in California, vintners and grape growers are looking for new water conservation strategies that will still allow production of high-quality grapes. UCCE advisors and specialists have been working for some time to address this very need. Twenty years of UCCE field trials have paid off in the form of what’s known as Regulated Deficit Irrigation (RDI). In a nutshell, RDI looks at how much water a grapevine needs and how much water the plant would get from nature, without irrigation. By studying numerous grapevine varieties in all seasons and climates, UCCE researchers have achieved a better understanding of how to irrigate in the most efficient way and still get top-notch results. The new strategy has been a huge success and has been widely adopted by growers.