What controls flowering in Waratahs - Deja vu for the faculty?

29 June 2011

The waratah is well known as the NSW floral emblem but is also a very striking cut flower. Commercially grown waratahs flower in spring within a 5-6 week window, producing bright red terminal flowers. Several cultivars of T. speciosissima and hybrids of T. speciosissima, T. mongaensis and T. oreades have been selected to provide an array of forms in whites, pinks and reds. Despite increasing domestic and export market demand, the waratah industry has failed to fulfil its potential in terms of producing large quantities of premium quality blooms that command high returns. A major impediment has been the inability to predict and manipulate flowering time to avoid oversupply in spring and to extend the season to supply major marketing events such as Christmas.

Based on work with other Proteaceous species including Banksia, there is evidence to suggest that flowering could be advanced or delayed to supply blooms out of season, when premium prices are be paid for red inflorescences. Understanding the mechanisms that control flowering will enable growers to select suitable cultivars and time the marketing of blooms to maximise profitability.

Extending the commercial waratah flowering season has long been a major goal for researchers at the University of Sydney. In the 1980s the Faculty's then Professor of Horticulture, Michael Mullins identified that waratahs initiate flowers in December, nine months before flowering in September. Then in the 1990s Dr Peter Goodwin, a Reader in Horticulture discovered that temperature played a big part in timing flowering, with southern plantations producing flowers later in the season. Despite this early work, precise information on the environmental cues which initiate and control flowering are unknown, resulting in unpredictable yields and profitability for the growers.

A new research collaboration between the NSW Wildflower Industry, RBG Trust, RIRDC and the University of Sydney led by A/Professor Robyn McConchie, will examine the contribution of temperature, day length, age, size and nutritional status of stems to flower induction, initiation and development in selected waratah cultivars. Based on that information, it will be possible to investigate the influence of growth regulators and canopy management in manipulating timing of anthesis. An understanding of the phenology of flowering will also assist in understanding the impact and mitigation of climate change on natural and commercial stands of waratah.

Waratah Research - Postgraduate Scholarship Available
A postgraduate research opportunity is now available working with the iconic Australian flower, the waratah. The Faculty of Agriculture, Food and Natural Resources has places and scholarships (equivalent to an APA) available for PhD students. Applications are now open. Please contact Ms Pamela Stern at

Contact: A/Professor Robyn McConchie

Phone: 02 8627 1045

Email: 03184d52186914200d5c4136020b040a303c280a522b194e530d4f4a37