Plants Proven To Beat The Heat In Drought Conditions

Want drought tolerance? Katrina Deluxe™ earned a Blue Ribbon™ in the UC Landscape Plant Irrigation Trials™.


Do you have customer landscapes with plants that struggle to survive during periods of drought? Then you might want to look into winners of the University of California Landscape Plant Irrigation Trials™ (UCLPIT). The UCLPIT trials were the first to schedule the irrigation frequency of a fixed volume of water based on reference evapotranspiration (ETo). In other words, the two-year trial program examines plant performance with deficit irrigation treatments and shade to determine which maintain high standards of aesthetic quality over the growing season. It actually began as a graduate student research project taken on by Karrie Reid in 2004 under the guidance of her advisor Loren Oki, UCCE Specialist at UC Davis.

Recently, two patented varieties from Dig Plant Company were awarded Blue Ribbons™ in the UCLPIT 2018-2020 trials for a high level of performance on low water: Lomandra longifolia ‘Katrinus Deluxe’, was evaluated in part shade, and Rhagodia spinescens ‘SAB01’ Aussie Flat Bush™ was evaluated in full sun. Both varieties were bred by Australian native Todd Layt of Ozbreed.

Katrina Deluxe™ is not only drought tolerant, but it’s also shade tolerant, heat tolerant, disease tolerant, and low maintenance. It looks like an ornamental grass all year with pine-green foliage and a weeping habit. Matures to roughly 3 ½ feet tall and a 3 ½ feet wide, and perhaps slightly larger under optimal conditions. At its healthiest when given only minimal irrigation. USDA Zone 7b -11 (evergreen 8a and, in some places, 7b in normal winters). Katrinus Deluxe is part of Dig Plant Company’s Tuffy Plant Collection™.drought

Aussie Flatbush™ is a low-growing, compact form of saltbush native to Australia and is a tough and drought tolerant groundcover option for Western US gardens in zones 9 – 11 (frost tolerant to approximately 25 ̊ F). Its blue foliage stands out in mass plantings, and it responds well to annual pruning or more often for a manicured look. It’s also fast to establish.

Other 2020 Blue RibbonTM winners at UC Davis included:

  • Buddleia × ‘SMNBDBT’ Pugster Blue®
  • Hypericum kalmianum ‘Deppe’ Sunny Boulevard®
  • Lippia ‘ECOLOPIA2’ Pink
  • ×Pyracomeles ‘NCXP1’ Juke Box®
  • Hypericum kalmianum ‘Deppe’ Sunny Boulevard®
  • Rosa ‘NOA168098F’ Flower Carpet® Pink Supreme

For the full list of over 40 low-water Blue Ribbon winners, click here. Three additional Blue Ribbon™ Winners were trialed at South Coast REC.