GA3 on young apple trees: rate, wetter and application frequency

2015–16 | Future Orchards® trial | Queensland | Stephen Tancred, Orchard Services

This Queensland Future Orchards® trial evaluates gibberellic acid (GA3) as a tool to encourage growth in young apple trees. The demonstration compares rate, wetter and number of applications, focusing on how spray-program design changes the vegetative response.

For young blocks, rapid but controlled canopy establishment can have a large effect on how quickly trees fill their space and reach commercial production. The trial therefore treats shoot extension as a measurable establishment outcome rather than simply observing whether a PGR produced visible growth.

The report provides a practical framework for growers considering GA3 in young trees: compare treatments against untreated trees, monitor extension growth, and interpret the response alongside irrigation, nutrition, tree training and general tree health. It is most valuable as a local demonstration of how PGR programs can be refined before wider adoption.