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.