Leucospermum species are temperate climate plants native to South Africa and have restricted production regions in Hawaii limited to elevations of 457 m or higher. This limitation and competition for land has been partially responsible to a decline in Leucospermum production in Hawaii. Agriculture land at lower elevations is more abundant and cheaper, and is an option for growing low elevation tolerant varieties. Breeding programs at the University of Hawaii at Manoa have focused on developing hybrids that will perform to commercial standards for plant growth, yield and quality, and grow at or near sea level. 14 hybrids of Leucospermum were trialed at 152 m elevation on Oahu HI. 10 hybrids exhibited adequate survival and were selected for continued trial. Weahter, plant growth (height and width), flower count, flowering seasonality, and plant health data were collected from 2021-2023. Flower length and quality data, and vase life data were collected in 2024. Average relative humidity was 79%, average monthly rainfall was 3.53 cm, and average temperature was 21.8 C with maximum temperature of 33.4 C and low of 14.2 C. The 10 hybrids all had acceptable fitness at 500’ elevation. Some hybrids showed more fitness than others. Hybrid 602 had the highest overall average health (3.8) and highest total flower count. Hybrids 620 and 626 also showed excellent fitness as well as highest flower counts. While none of the hybrids are considered unfit for production in similar conditions, some did perform less well. Hybrid 88 and Hybrid 633 had the lowest average health at 3.0 followed closely by Hybrids 583 (3.2), 679 (3.3), and 563 (3.3). These varieties also had some of the lowest total flower counts. All of the hybrids in this study are considered potential candidates for release and continued trialing. Future work can include long term trialing of these plants, and trialing at different microclimates across the State.
