A New Method Facilitates Bermudagrass Growth During Spring Transition

The spring transition in bermudagrass (Cynodon dactylon) overseeded with perennial ryegrass (Lolium perenne) remains a major challenge in turf management due to persistent competition from the cool-season species. Conventional practices such as core cultivation can damage bermudagrass stands and delay recovery. This study evaluated a novel, non-damaging approach using a yeast-based fertilizer to enhance bermudagrass regrowth during the transition period. The fertilizer consisted of Saccharomyces cerevisiae and glucose applied as a soil drench. A greenhouse experiment was conducted over two years (2023–2024) using “Yangjiang” bermudagrass overseeded with “Wintergame” perennial ryegrass. Five treatments were compared: control (0 g·m−2 yeast + 0 g·m−2 glucose), yeast alone (200 g·m−2), and yeast combined with glucose at 100, 200, or 400 g·m−2. Growth parameters were assessed at 7, 14, and 28 days after treatment. The application of 200 g·m−2 yeast + 200 g·m−2 glucose yielded the most significant improvements. At 14 days, bermudagrass shoot density and turf cover significantly (p < 0.05) increased by 45.81% and 129.51%, respectively, compared to the control. By 28 days, aboveground and belowground biomass significantly (p < 0.05) increased by 308.14% and 51.35%, respectively. Root system architecture was also significantly (p < 0.05) enhanced, with total root length, surface area, and volume rising by 62.05%, 40.59%, and 63.51%. These results demonstrate that yeast fertilizer strongly promotes bermudagrass shoot and root growth during spring transition, likely by generating CO2 to improve soil porosity without physical turf injury. This method provides a practical and complementary strategy for managing overseeded turfgrass systems.