This research described the preparation of polyvinyl alcohol/kenaf fiber composites with entrapped urea. At the first stage of study, the water solubility, release behavior, chemical properties, and thermal stability of the composites were evaluated. In a wet environment, urea was released from the composites through its dissolution in water. The evidence of degradation of polyvinyl alcohol could be monitored by using FTIR spectroscopy. In addition, cracks and fungal growth on the surface of the materials could be clearly observed under the microscope. The rate of degradation could be monitored from the weight loss of the sample, which increased significantly when submerged in water. To slow down the disintegration under conditions of excess moisture, the composite was slightly cross-linked with methylene diphenyl diisocyanate (MDI) at the second stage of the study. From the field test study, it was observed that the use of this kenaf reinforced biocomposite has successfully protected the seedlings of long bean from moisture loss. At the end of their life, the release of the the kenaf fibers from the degradation of polyvinyl alcohol matrix enable the kenaf fiber to serve as soil fertilizer to the plant. There was no any undegradable polymer waste was leave for disposal. This study showed that crosslinked kenaf reinforced biopolymer composite could serve as promising mulches to replace existing petroleum base polyethylene mulch film in the market.