Mamaki – Fertilization and branch bending trials for continuous leaf flush and soil fertility

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2020: $20,000.00
Projected End Date: 08/31/2021
Host Institution Award ID: G273-20-W7900
Grant Recipient: Mamaki Ola
Region: Western
State: Hawaii
Principal Investigator:
Dr. Ming Wei Koh
Center for Getting Things Started


  • Additional Plants: native plants


  • Crop Production: agroforestry, nutrient management, other
  • Education and Training: on-farm/ranch research

    Proposal summary:

    Māmaki (Pipturus albidus) has recently become a high demand commodity crop (Sugano, et. al, 2019). Māmaki, an endemic Hawaiian understory plant of native forests from sea level to elevations up to 6,000 feet thrives in 40%- 60% shade cover (Krauss, 1993, 2001;Wagner et al. 1990). In order to scale up māmaki production in non-forest settings, there are two problems to solve. First is providing partial shade to the growing māmaki, and the second is keeping the māmaki in continuous leaf flush

                The three approaches to the problems:

    1. Grow the māmaki in an agroforestry setting (as suggested by Sugano, et. al.) intercropping with fast growing moringa (Moringa oleifera)and pigeon pea (Cajanus cajan), and ground cover of butterfly pea (Clitoria ternatea);
    2.   Branch bending (i.e., ground layering) of māmaki to encourage new stem and leaf growth; and 
    3.   To sprench (foliar feed / soil drench combination) with nutrient rich compost teas. 


    There is a dearth of research and outreach on māmaki. We propose to:

    1.   Gather the Shaka Beverage Farm Hui in Hilo to share and openly discuss the results of the research; followed by 
    2.   Two field days open to all farmers – one each at Māmaki Ola and Wrenn farm; and
    3.   Work with a small group of K- 12 educators to create māmaki related lesson plans and thus educate the next generation on sustainable agriculture. 


    This project intends to show the potential of growing māmaki in a small-scale, regenerative, beyond sustainable manner while decreasing farm inputs and working towards economic abundance for local farmers.

    Project objectives from proposal:

    1.   Agroforestry system for commercial māmaki farm: determine optimal fast growing shrubs/trees with market value (e.g., moringa and butterfly pea) and with fertility value (pigeon pea and butterfly pea – nitrogen fixers) for intercropping with māmaki – modeling agroforestry systems, providing shade to the māmaki, and ground cover/compost cropping;
    2.   Branch bending: determine if branch bending (i.e., ground layering) is a viable method to encourage new stem and leaf growth, and

    3.    Continuous leaf flush: determine optimal fertilization methods to keep mature māmaki plants in continuous leaf flush.

    Mamaki Ola Farm – Latitude 19.398242, Longitude -154.925791.

    Wrenn Farm  – Latitude 19.566509 Longitude -154.952637

    Drought wiped out 50% of māmaki seedlings planted in the 2018 season. 

    The technical advisor will visit each farm on alternating months. 

    Both producers, working in tandem with one another, will be on site during advisor visits to each respective farm to: 

    1) collect data and immediately input the data onto a Google Sheet in a shared Google Drive, 

    2) discuss progress and process, and 

    3) brainstorm ideas. 

    Mr. Mermel and Dr. Koh will be responsible for note-taking and documenting the process.

    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.