Improving Groundcover Establishment Through Seed Rate, Seed Ratio, and Hydrophilic Seed Coating

Kentucky bluegrass (KBG) is well-suited as a perennial groundcover in corn production due to its vigorous growth during the fall and spring and its natural dormancy during the summer, aligning with the corn growing season. However, seeds of KBG germinate slowly, potentially resulting in poor stand establishment in the Midwest, USA. This study was conducted to assess the effect of the seeding rate, the seed ratio in a perennial ryegrass/KBG mixture (PRG:KBG), and seed treatment on KBG percentage groundcover, green rating, the red/far-red ratio, soil temperature, soil moisture, and summer biomass. The split-plot design consisted of KBG seeds treated with the HydrolocTM hydrophilic polymer and untreated seeds with seeding rates and ratios in a randomized design. Hydroloc™ seed treatment showed a significant difference in the fall percentage of groundcover but did not affect the spring groundcover. The seed ratio had a significant effect on the fall and spring groundcover, with a ratio of 1:1 (PRG:KBG) performing best, followed by 1:3, 1:5, and 0:1. The seeding rate was also significant, with 44.8 kg ha−1 having the highest groundcover, followed by 22.4 kg ha−1 and 11.2 kg ha−1. The red/far-red readings, which reflect plant density, gave corresponding results to the percentage of groundcover. The Hydroloc™ hydrophilic polymer increases the groundcover percentage by improving KBG establishment. These results are important for farmers and seed companies interested in using KBG as a perennial groundcover in corn production systems. We recommend a seed ratio of 1:1 (PRG:KBG) and a seeding rate of 22.4 kg ha−1 to provide a dense and rapid-establishing groundcover that is also financially viable for the farmer.