Researchers at the University of Hawaiʻi at Mānoa (CTAHR) have achieved a breakthrough in floriculture by breeding new “tropical” pincushion protea (Leucospermum) hybrids that bloom near sea level, reducing local reliance on imported flowers.
“These new genetic combinations allow growers at all elevations to harvest flowers nearly year-round. They also make colorful contributions to urban, commercial and resort landscapes,” said CTAHR Professor Kenneth Leonhardt of the Department of Tropical Plant and Soil Sciences.
Overcoming mountain-high barrier
Pincushion proteas are native to South Africa and need cool night temperatures to grow their famous flower buds. 贬补飞补颈ʻ颈’蝉 commercial protea production was limited to elevations between 2,500 and 4,000 feet, primarily in Upcountry Maui and on Hawaiʻi Island’s high-elevation areas.
This kind of agricultural land is scarce and expensive, pricing many local cut-flower growers out of the protea market.
Science behind breakthrough
Led by Leonhardt, the research team conducted years of warm-temperature tolerance trials, as well as trials at low elevations such as Two Bee’s Protea Farm on 翱ʻ补丑耻’蝉 North Shore. He identified three seldom-used species as key sources of heat resistance and used that insight in a successful, years-long breeding program.
These new varieties of protea have several standout traits:
- Created to grow abundant floral buds in warmer, coastal environments without requiring cool mountain nights.
- Selected for vibrant colors, extended blooming seasons, straight stems and reduced leaf/stem fuzz.
- 18 of the new cultivars have been internationally registered in Stellenbosch, South Africa, establishing CTAHR as a premier global leader in tropical ornamental breeding.
Benefits to local growers
The college and its partners have distributed more than 11,000 of the newly bred plants to 33 Hawaiʻi Island farms. Most of these distributions have been in collaboration with the Hawaiʻi Tropical Flower Council through their Import Replacement Program, funded by a grant from the Hawaiʻi Department of Agriculture and Biosecurity.
Leonhardt and his team are also working with producers of container landscape plants to establish the new tropical proteas in home gardens and commercial and resort landscapes.