Vitex agnus-castus 'PIIVAC-I'

Summary

UC Davis is located in Davis, California, this site has a silty clay loam soil and plants are irrigated with potable water. More information about the field sites is located in the Nuts & Bolts section.

Delta Blues chaste tree was the star of the 2018 trial year: a crowd favorite at the open houses and with staff.  Open house participants were universally enthusiastic about this smaller version of the chaste tree with remarks including “would buy”, “spectacular specimen”, and “WOW!”  It was the plant most people said they would use or recommend to clients with the space for it.  This large, informally shaped shrub began blooming in June and was smothered in large purple panicles by July. It continued to bloom lightly through the rest of summer with a final surge of bloom in October.  Plants were untouched by disease and displayed only minor insect damage later in the season which did not affect overall appearance ratings that ranged from very good to WOW (excellent) throughout the season on all irrigation levels (Table 19a).  There were no growth differences between treatments, with those on the Low irrigation level having a slightly, if insignificantly, higher overall appearance rating than the other treatments. This is definitely an excellent large flowering shrub for the Low water landscape, and like other Vitex, could be pruned early on to shape into a small tree as well.