ORGANIC MULCHES: WEED CONTROL, MOISTURE RETENTION, SOIL TEMPERATURE, AND CROP YIELD

Abstract

This paper investigates the use of locally available organic mulch and organic fertilizer for the production of sweet corn in Barbados. It focuses primarily on the impact of locally produced coconut fiber, wood chip, and green waste mulches on sweet corn yield, weed control, moisture retention and soil temperature. The performance of these organic mulches is compared to synthetic mulch and a control (unmulched). The effect of the amendments and cropping density are also assessed. The variety of sweet corn grown was Golden Sweeter 93. Organic pest management practices were utilized throughout the production period. The use of organic mulches did not significantly increase yields in comparison with the control. Cropping densities used in the trial had no significant impact on yield. Weed control among all organic mulches was significant. Coconut fiber and wood chip provided the best weed control among these organic mulches. Organic mulches had 5-10 times less weeds than the control before first weeding. Weeds such as Commelina elegans, Euphorbia heterophylla L., and Mimosa spp. persisted within organic mulch treatments but below economic damage threshold levels. All treatments lead to an increase in moisture retention when compared to the control. Coconut fiber and Wood chip performed the best among the amendments in relation to water retention. Soil Temperature was significantly reduced by all organic treatments, a reduction of 1.3-1.9 °C. The Green Waste treatment resulted in the lowest average soil temperature. The implications and details of these observations in relation to organic crop production, weed management, and soil fertility management are discussed.