Best Management Practices for Establishment of Salt-Tolerant Grasses on Roadsides

Roadsides are a unique growing environment for turfgrasses and can be a challenge to establish and maintain. The University of Minnesota turfgrass research program has been investigating low-input turfgrasses that are better adapted for roadsides and our previous research project identified a new mixture for use on Minnesota roadsides that was able to perform adequately under pressure form road salt (MNST-12). As this new mixture was used, it became apparent that more research was needed to better understand how to improve establishment and performance by adjusting typical roadside maintenance practices. In this project, we developed a series of experiments addressing three areas: (1) pre-establishment soil amendments; (2) planting date; and (3) watering during establishment. We found that soil amendments had little effect on roadside turf performance. We found that seeding of low-input roadside mixtures such as MNST-12 should be performed in late summer, while sodding can be done throughout the growing season, assuming that soil moisture is properly maintained. Finally, based on our findings, we recommend that current MnDOT specifications for watering of new roadside turf installations should be changed, especially for mixtures with high proportions of fine fescue.