The Department of Agriculture and Fisheries (DAF) is working in partnership with Australian mango growers to improve adoption of next-generation, intensive mango systems and help improve productivity and profitability.
More mangoes, but more profit? It is the question many growers have asked. There are many good reasons why older mango orchards were planted at wide spacings and inevitably grew into tall trees. These include; vigorous varieties (eg. KP), difficulty controlling plant vigour using available methods (eg. cincturing, growth regulators, water/nutrition management), high pruning costs, the use of existing wide-bodied farm machinery, and the need to allow light to enter orchards to achieve good flowering, fruit set and fruit quality including blush.
Today, tall trees are rapidly becoming a thing of the past, and many growers are now managing their orchards (even older, wider spaced orchards) by mechanically hedging their trees back to 2.5-4m height every year. These changing practices are often for cost savings, harvest efficiency and workplace, health and safety purposes.However, maintaining these smaller trees at the traditional wide inter-row spacings of 8-10m is an inefficient use of light and site resources.
Figure 1. High-density Calypso® trees (4 x 2m = 1242 trees/ha) at Walkamin Research Facility.
Results from the Small Trees High Productivity Initiative at the Queensland Department of Agriculture and Fisheries (DAF) Walkamin Research Facility near Mareeba, are demonstrating that mangoes can be grown with high productivity at high densities. These results apply to both traditional hedging (Figure 1), as well as trellising methods. Varieties studied include Calypso®, NMBP1243 and Keitt. Seven years of yield and management system input data have now been collected.
(Calypso® yield data is presented in Figure 2). These early results are showing that the extra costs of establishing trees at higher densities can be quickly recouped via significantly increased early yields per hectare, resulting in increased orchard profitability from an early age.
Figure 2. Calypso yields (T/Ha) to age 6 years, for 4 mango density systems at the DAF Walkamin Research Facility.
Economic data of expenditure and revenue up to age seven years has now been collected for trees grown at 207, 414 and 1242 trees/ha using traditional hedging methods, and 1188 trees/Ha using trellising methods. This economic data has been modelled and projected forward to an orchard age of 30 years. The results of this analysis are currently being ground-truthed with grower and industry advice and a full economic report on the early profitability of mangoes grown at different densities will be produced by the end of 2020.
The economic analysis study is a key output from the 3-year project ‘Transforming Mango Futures’ funded through the Cooperative Research Centre for Developing Northern Australia (CRCNA) and including project partners DAF, Australian Mangoes, Manbulloo Ltd and Marto’s Mangoes. The Walkamin high-density trials were established within the ‘Transforming subtropical and tropical tree productivity project’ a collaboration between Hort Innovation using the across industry R&D levy and co-investment from DAF, the Queensland Alliance for Agriculture and Food Innovation and funds from the Australian government.