Enhancing Phytonutrient Content, Yield and Quality of Vegetables with Compost Tea in the Tropics

2010 Annual Report for SW07-073

Project Type: Research and Education
Funds awarded in 2007: $162,500.00
Projected End Date: 12/31/2011
Region: Western
State: Hawaii
Principal Investigator:
Dr. Theodore Radovich
University of Hawaii, Manoa

Enhancing Phytonutrient Content, Yield and Quality of Vegetables with Compost Tea in the Tropics


Accomplished tasks in 2010 were focused on completing greenhouse experimentation, on-farm trials and workshop planning in preparation for the project completion in June 2011.

Objectives/Performance Targets

1) Quantify the independent and interactive effects of compost quality and vegetable type under synthetic and organic fertilization on yield and phyto-nutrient content of model root, fruit and leaf vegetables.

2) Determine, at the whole-farm level, the effect of compost tea applications on yield, phyto-nutrient content and profitability on commercial vegetable operations on three islands in Hawai’i.

3) Build and enhance the capacity of at least 300 growers to effectively employ compost tea to increase vegetable yield and phyto-nutrient content on their farms.


Accomplishments in 2010 include:

– Completion of three greenhouse experiments to understand the mechanisms involved in compost tea action on plant growth. (attachments 1 & 2).

– Completion of on-farm trial to evaluate impact of tea made from farmer-produced compost (attachment 3).

– Two scientific presentations at the American Society for Horticultural Science annual meeting(attachment 1 & 2).

– Three extension presentations to a total of 100 growers and agricultural professionals(e.g. attach 3).

-Submission of one manuscript to peer-reviewed journal.

-Progressed with planning for February and April 2011 workshops on Maui and Hawaii Islands.

-Progressed with development of compost tea handbook.

Impacts and Contributions/Outcomes

Impacts and Outcomes for this reporting period:

1) Improved decision-making skills regarding tea production and application of more than 100 growers and agricultural professionals currently using compost tea.

2) Increased awareness of the potential of compost tea and other biologically derived inputs to improve farm sustainability among the broader farming community.

3) Significant contribution to the small but growing body of scientific knowledge regarding compost tea, particularly as it pertains to enhancing human health value in tropical systems.

Expected Medium-range outcomes

1) Increase productivity and profitability of sustainable farming operations.

2) Greater use of compost tea and other biologically derived inputs by the general agricultural community.

3) Increase cooperation between the University, industry, growers and other stakeholders.

Expected Long-Term Measurable Impacts (modified):

1) Improved productivity and profitability (current $5 million, farm gate) by the majority of the more than 120 certified organic growers on almost 1,000 acres in Hawaii.

2) Chemical fertilier use reduced by at least 25% on 50 conventional farms.

3) Attendance of 100 growers of at workshops and field days.

4) One thousand hits/month at educational websites.

5) Featuring of locally grown produce as grown for maximum health benefit by local restaurants and retail outlets.


Kelly Lange

Hawai'i Organic Farmers Association
PO Box 6863
Hilo, HI 96720
Michael Alms

[email protected]
Growing Solutions
1939 West Second Avenue, Suite B5
Eugene, OR 97402
Office Phone: 8087750616
Tane Datta

[email protected]
Adaptations, Inc.
7 Telephone Exchange Rd
Honaunau, HI 96704
Office Phone: 8083289044
Gerry Ross

[email protected]
Kupa'a Farm
Na’alae Road
Kula, HI
Office Phone: 8088760678
Wei Chong Ho

Ho Farm
PO Box 569
Kahuku, HI 96731
Stephen Talcott

[email protected]
Texas A&M University
Department of Nutrition and Food Science
Centeq Center Room 220F
College Station, TX 77843
Office Phone: 9798624056