The Mango Loa Project

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2017: $19,878.00
Projected End Date: 10/31/2020
Grant Recipient: Umi Martin
Region: Western
State: Hawaii
Principal Investigator:
Umi Martin
Umi Martin


Not commodity specific


  • Crop Production: fertigation, grafting
  • Education and Training: demonstration, farmer to farmer, networking, on-farm/ranch research, workshop, youth education
  • Production Systems: Ultra High Density Planting


    Improving Hawaii’s mango industry by introducing and comparing two innovative techniques that have increased the yield and quality of fruit production, while improving on efficiency and management of the orchard.  This project demonstrates the ultra high density plantation (UHDP) technique on a half acre field with 310 trees (10 rows with 31 trees) and the open Tatura trellis system on a 1/2 acre field with 300 trees (five rows of trellis with 60 trees per row).  This project evaluates the costs of installation per acre, the advantages and disadvantages of these systems versus the standard methods, the expected return on investment, potential increase of production, labor demands, and orchard management. 


    Project objectives:


    The objective of the Mango Loa project is to improve the yield and quality of Hawaii’s mango industry by demonstrating and comparing two new innovative orchard management systems for tropical fruits, these are the ultra high density plantation and the open Tatura trellis system.  This project will cover the first three years, beginning with the installation following up with the pruning and training demands leading up to the start of production at three to four years.

    The mango tree is a sub-tropical evergreen tree that is widely dispersed throughout the tropics.  The trees are long lived, often over 100 years while still producing fruit.  If left unpruned, trees will grow between 60 and 100 feet tall in 25 years. Traditionally, mango orchards were planted at a density of 50 trees per acre, with a spacing of 25 feet by 25 feet.  Orchard maintenance is difficult and labor intensive.  Pruning requires climbing trees, tall ladders, and pole saws, which increases the hazards on the job and the cost of production.  Another method of pruning utilizes a tractor attachment with rotating blades which allows for mechanical pruning; this method is very fast and efficient, but also very cost prohibitive, limiting its use to large commercial orchards.  Harvesting requires long pickers that often causes blemishes on the fruit and is prone to knocking down adjacent fruits.  Mechanical lifts are utilized to facilitate harvesting and pruning, but again this equipment is expensive and only used by large orchards.  Canopy maintenance is limited and pest and disease management is very difficult.  Maintaining the ground cover and weeds is time consuming.   The standard mango orchard takes seven to ten years for the trees to reach maximum production.  All of these things add up to a lower quality fruit, a greater cost of production, and a longer wait for the orchard to to reach maximum production.  A realistic expectation for mango production is two to five tons per acre, and the Food and Agriculture Organization (FAO) report the global average for mango production at 3.5 tons/acre.

    The ultra high density plantation (UHDP) method has been in use for around a decade.  Where it was first developed is hard to pinpoint, but India, Australia, Israel, South Africa, and China are a few of the countries that utilize this method for mango production.  Planting densities over 300 trees per acre is considered ultra high density.  UHDP is very similar to the standard mango orchard except that ten times the amount of trees are planted in the same area.  The idea behind the increased density and the short trees is to lessen the demand on labor, while maximizing the use of available land and resources.  All work is done from the ground, everything is done with simple hand tools, and in India they say that one person can manage up to 10 acres by his or herself.  Through trials done in India and Australia, we know that mango trees thrive under heavy pruning and aside from lessening the demand on labor, there was also an increase in yield and quality of the fruit, increasing production to 8 to 12 tons per acre, while shortening the time to maximum production from 7 to 10 years to 3 to 4 years. 

    The Tatura trellis system has been around for about 30 years and was developed at the Tatura research institute in Victoria, Australia, with the goal of improving productivity and sustainability of temperate zoned fruits and through trial and error the trellises were a success and the practice has been accepted worldwide.  In 2006, farmers in North Queensland, the tropical area of Australia, began adapting the trellis to tropical fruits to try and protect their orchards from severe storms, after a tropical cyclone had devastated the fruit orchards in the area. Then, in 2011, Tropical cyclone Yasi, a very large cyclone, hit North Queensland again, but this time, the trees that were on trellises survived.  Since then, Australia has dedicated a lot towards research and trials to improve and adapt the open Tatura trellis system for tropical fruits.

    Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.