ASHS 2025 Conference

Sweet Corn (Zea mays) is a popular warm season specialty crop grown in the United States and around the world. Sweet corn production can encounter obstacles including weed competition and nutrient losses, particularly nitrate leaching. This study explored the influence of third-year clover living mulch systems on organic sweet corn production, and the impact of historic in-row soil management practices on sweet corn growth and yield. Conducted in 2024 at the SDSU Southeast Research Farm, Beresford, SD, USA, this research investigated the impact of established clover living mulch on ‘Who Gets Kissed©’ sweet corn (High Mowing Seeds). Two years prior to sweet corn planting, three clover cultivars were established: ‘Domino’ white clover (Trifolium repens), ‘Aberlasting’ white x kura clover (T. repens x ambiguum), and ‘Dynamite’ red clover (Trifolium pratense), which were compared with a bare-ground control. During the past two seasons, within each clover whole plot, four in-row soil management subplots (till, till landscape fabric, no-till, no-till landscape fabric) were established. The established plots were planted with acorn squash (cucurbita pepo) in the first year, followed by fall cabbage (Brassica oleraceae var. capitata) in the second. Prior to sweet corn production, all treatments were strip-tilled to temporarily delay clover and prepare a planting bed for direct seeding of sweet corn with a single row planter. No landscape fabric was used in-row to align with medium to large scale production practices. Till treatments were weeded with a stirrup hoe and represented tilled cultivation. No-till treatments were hand weeded with the proper hand tool to minimize soil disturbance. Sweet corn data was collected to understand the impact of clover variety and soil management practices on crop health, weed suppression, and yield. Yield was graded in accordance with the USDA Marketable Standard for sweet corn cash crop production. Weed biomass decreased as the season progressed and sweet corn canopy closed; however mid-season drought conditions decreased clover growth. Prior years of soil management did not affect yield and production (p ≤ 0.8), but clover living mulch systems did (p ≤ 0.04). Over 50% of the graded sweet corn was in the US No1 and US No 2 categories. Bare ground treatment plots were first to reach maturity and produced the highest percentage of marketable ears. Farmers who are interested in growing sweet corn could utilize living mulch systems after key considerations such as water availability, early season maintenance, and scale of production.