2006 Annual Report 4d.Progress report. This report serves to document activities conducted under a non-funded cooperative agreement established under the supervision of ARS scientists Dr. Charles Webber and Dr. Angela Davis, in cooperation with organic producers Joe and Victoria Townsend. Additional details of research can be found in the report for the parent CRIS 6222-21220-002-00D, Yield and Quality of Vegetable Crops in Conventional and Organic Production Systems. The objective of this project was to investigate the two foremost concerns of organic producers, i.e., suitable organic varieties and weed management. Organic qualified cultivars of watermelon were established under a system that included weed management using rye and legume cover crops. Transplants of six cultivars, including diploids, triploids and heirloom, watermelons were produced using organic procedures and materials. The cereal and legume cover crops were flail mowed prior to transplanting watermelon seedlings into the mulch. No-till methods for production were used. Cultivars responded to treatment and differences in fruit size and yield were noted.