Final Report Saratoga Horticultural Research Endowment 2013-2015 Ornamental plant trials for the new California landscape: Evaluating industry introductions for sustainable characteristics on reduced water Principal Investigator: Karrie Reid, UCCE Environmental Horticulture Advisor, San Joaquin County 2101 E. Earhart Ave., Ste 200 Stockton, CA 95206-3949 (209) 953-6109 office (209) 953-6128 fax
[email protected] Co-Investigators: David W. Fujino, Ph.D., Director, California Center for Urban Horticulture, UC Davis Lorence (Loren) R. Oki, Ph.D., CE Specialist, Dept. of Plant Sciences, UC Davis Jared Sisneroz, Staff Research Associate, Dept. of Plant Sciences, UC Davis Executive Summary In these trials 16 perennial landscape plant species, (9 new cultivars and 7 underutilized species/cultivars), were evaluated for overall performance on a range of reduced irrigation levels in clay loam soil in the hot interior Central Valley of California. All plants were grown in- ground for 2 years; 12 of the species in full sun and 4 under 50% shade. Planting in October 2013 was followed by an establishment period of irrigation at 80%-100% of reference evapotranspiration (ET0) and 25% management allowable depletion through April 2015. Plants were then subjected to 1 of 4 different levels of reduced irrigation at 20%, 40%, 60%, or 80% of ET0 during the dry season through the first week of October 2015. During the deficit irrigation season they were evaluated across treatments for growth, health and vigor, overall appearance, flowering, pest tolerance, and disease resistance. From these assessments, irrigation recommendations are made for their use in the landscape. Introduction Plant performance trials are a critical step in the introduction and promotion of new or unfamiliar ornamental plants.