Completed project
Optimising cherry fruit set, crop load, fruit nutrition and size - phase 2 (CY12003)
Publication date: June 24, 2015
Delivery Partner: University of Tasmania
This project involved three streams of research, carried out over four years from 2012 to 2015 to research cherry yield and quality.
Plant bioregulators for optimal crop load management
Fruit set affects both yield and fruit quality, hence is a core issue of profitability for growers. Inadequate fruit set leads to low yields and a high incidence of fruit cracking, while excessive fruit set leads to over-cropping and undersized, soft fruit. This study investigated both of these problems.
Researchers looked at the effects of bioregulators, including Retain, on fruit set, and made a comparison of two rootstocks, Gisela and Colt.
Key findings included…
Girdling and floral biology for prevention of fruitlet drop and improved fruit quality
Fruitlet drop is an issue impacting the profitability of the cherry industry, with particular varieties showing enhanced susceptibility.
This component of the project examined the role of carbohydrate availability in fruitlet drop and post-harvest fruit quality in Kordia and Lapins sweet cherry varieties.
Starch and soluble sugar concentrations in branch, trunk and root tissue were measured regularly throughout the growing seasons of 2012/13, 2013/14 and 2014/15.
Normal transport of carbohydrates was disrupted five weeks after full-bloom by applying trunk girdling and limb defoliation treatments, and the rate of flower and fruitlet drop was monitored.
Researchers found that girdling significantly reduced root starch reserves, and while it reduced fruit drop in Lapins, it had no effect in Kordia. Girdling in Kordia resulted in firmer, sweeter and larger fruit that had better post-harvest shelf life.
Fertigation for fruit quality
Nutrient management is a critical component of commercial sweet cherry orchard production, as each nutrient plays an important role in the development and quality of sweet cherry fruit.
Whilst fertigation is commonly practised by cherry growers in Australia, research into optimal nutrient supply to meet tree demands is limited and the effects of oversupply of pre-harvest nutrition on fruit quality are virtually unknown.
Even less is known about the influence of micro-element nutrition on sweet cherry fruit quality and which is the best method of application.
This component of the project investigated the role of nitrogen and potassium fertigation on sweet cherry fruit quality and post-harvest shelf-life whilst at the same time shed light on the role of pre-harvest micro-element nutrition on fruit quality. This project included data from five separate trials conducted over four seasons.
Findings were complex but high-level results included…
Download these fact sheets based on the research findings:
This project was a strategic levy investment in the Hort Innovation Cherry Fund
© 2026 Horticulture Innovation Australia Limited.
Related industries
