Organic Farming in the Tropics with Legume Groundcover

Project Overview

Project Type: Farmer/Rancher
Funds awarded in 2005: $8,107.00
Projected End Date: 12/31/2006
Region: Southern
State: Puerto Rico
Principal Investigator:


  • Additional Plants: native plants, ornamentals
  • Animals: bees


  • Crop Production: conservation tillage
  • Education and Training: decision support system, demonstration, display, extension, farmer to farmer, on-farm/ranch research, participatory research, study circle, workshop, technical assistance
  • Natural Resources/Environment: biodiversity, habitat enhancement, soil stabilization, wildlife
  • Pest Management: mulches - living, trap crops, weed ecology
  • Production Systems: holistic management, permaculture
  • Soil Management: green manures, nutrient mineralization, soil quality/health
  • Sustainable Communities: new business opportunities, partnerships, public participation, community services, employment opportunities, social capital, social networks, sustainability measures

    Proposal summary:

    The general problem we are addressing is the improper use of agricultural land and the consequent effects on soil conservation and water resources. The principal reservoirs of Puerto Rico are rapidly losing their water storage capacity because of high rates of sediment influx and accumulation. In our area of Utuado, for example, the Lago Dos Bocas reservoir has over one half of its storage capacity since it was first measured in 1942. Erosion mitigation is essential to preserve the existing and future reservoirs. A mayor cause of erosion is agricultural land use without conservation practices, especially on our typically steep mountain terrain where the main crop is sun-grown coffee. Our organization is involved in efforts to model appropriate agricultural land use, in particular, through the cultivation of shade coffee. We are now in the fourth year of our Shade Coffee Reforestation Project consisting of 13 acres of shade coffee under plantain trees that will provide temporary shade during the growth process of leguminous trees that we have planted in this area (every 35 feet). Last year, through the support of a SARE Producer grant, we attempted to take this project a step further by producing an acre of organic coffee. An important component of this project was establishing a groundcover with arachis pantanal, called “mani pantanal” in Puerto Rico, for weed control. This was the most difficult part of our project. The great diversity of weeds and the excellent conditions for their growth makes their control one of the greatest challenges for organic farming in the tropics. As we sought to overcome this problem with groundcover, the small plants we established in the nursery were unable to compete with the aggressive tropical weeds. We were eventually forced to use chemicals on the weeds so that the groundcover could take hold. Though the rest of our project was successful, this failed component frustrated our attempt to grow organic shade coffee. Through Professor Grisely De Jesus, who teaches Agricultural Technology at the University of Puerto Rico, we learned of a different method for the propagation of “mani pantanal.” She used this method successfully in an experiment she conducted with her students. It consists of establishing “carpets” of “mani pantanal” in specially designed, temporary nurseries. The method is very low-cost and requires a minimal amount of labor. We intend to implement the “carpet” method on the same acre we used for last year’s SARE project. We will take advantage of the efforts and resources that were already dedicated to establishing an acre of organic coffee, which except for the ground cover, is doing well. Before we begin, we will photograph the area and measure exactly how many square feet of ground cover we now have. The degree of success will be measured by comparing the area, in square feet, where the “mani pantanal” takes hold in comparison to how much of it took hold as a result of our previous effort. We will also measure the costs in materials and labor, against last year’s costs. These and all other comparables of each project will be displayed in a table for an overall view of the advantages of one over the other.

    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.