Some of the manipulation practices are listed below. More information is provided in each heading in the pages that follow.
- Flower suppression
- Chemical thinning
- Hand thinning
- Harvest timing
In the south west of Western Australia floral initiation of citrus usually occurs between June and July however identifying the difference between vegetative and floral shoots cannot be determined until early spring.
Many factors can influence flowering of citrus such as:
- past physiological history of the tree
- water stress
Gibberellic acid (GA) inhibits flower initiation in citrus, and has been used in other citrus growing countries for this purpose for a number of years. Ralex® is presently the only registered gibberellic acid compound for flower suppression in Australia where it is registered for use in both navel oranges and mandarins.
Leafless inflorescences produce a lot of white blossom but few leaves and produce smaller and less desirable fruit than leafy inflorecences which produce fewer flowers but fruit of better size. GA applications during flower initiation have been shown to reduce the number of leafless inflorescences and increase the more desirable leafy inflorescences which produce larger fruit.
The objective of flower suppression is to manipulate the forming bud into a vegetative state before any determination of floral parts has occurred.
Applications of GA should be made as directed on the label and be trialed on small areas to fine tune the technique on your own property.