Aspects of Macadamia Flowering and the Applications to Canopy Management

Abstract

Macadamia is a subtropical, evergreen tree which flowers in response to cool temperature, producing racemes that originate from axillary buds. The physiology of macadamia flowering, including some new data, and applications to canopy management are discussed. Floral initiation is also reliant on axillary bud release, which is affected by the timing of vegetative growth and characteristics of the stems. Other endogenous signals, including signals from the fruit, may also be involved. The most common form of canopy management in Australian macadamia orchards is mechanical hedging. Well timed autumn hedging or hedging in early winter would ensure the absence of immature vegetative flush that has the potential to suppress flowering. The relationship between flowering and yield in macadamia is largely unknown, so increasing flowering may not necessarily increase yield as with some other subtropical and tropical tree crops.