Using native grasses is a great idea for new – or old – housing developments. Once the areas of native grasses are established, they will have thick surface coverage of healthy, green grass. Maintaining these grasses can be managed in the same manner as turf grasses. Mowing and weeding these areas will provide long-term stands of these diverse, native grasses.
In areas that can’t be mowed along stream banks and drainage areas, pollinators can help keep the native grasses thriving. Those pollinators are bees, butterflies, beetles, and flies that help fertilize the native species and keep them healthy throughout the year. Native species are also known to develop their own defenses against pests and diseases. The more diverse the vegetative community, the healthier the ecosystem will be for that area. Vegetation diversity creates habitats for a wide variation of soil biology, beneficial insects, and other wildlife species.
However, incorporating native grasses into recently disturbed soil is not as easy as it sounds. These grasses require healthy topsoil to germinate. I recently worked with a subdivision in Colorado to plan the best steps to ensure the success of their native grasses.
The developers planned their work and preserved the healthy topsoil before excavating began. They kept the topsoil separate from the underlying subsoil when clearing the land for development. When it came time to plant the native grass species, they replaced the original topsoil. That means the grasses will have a better chance to germinate and grow in those areas. Topsoil contains organic matter, plant available nutrients, and geochemical complexes that allow for better moisture retention. These properties aid in the germination of native grass seeds and decrease the need for fertilizers and amendments.
As well as needing healthy topsoil, native grass species need adequate moisture to germinate and propagate the landscape. Many of these native grass species germinate in the early spring (March through mid-May), while others will germinate in the cool season of mid-autumn (mid-September through October). It’s during these time frames when the soil temperatures are just right and soil moisture is at the appropriate levels. Native grass species will go dormant in the heat of the summer and in during winter months. Native grasses can also adapt to the soil biology of the area and not be affected by fungus or wet spots. Once native grasses are established, they will adapt to low moisture needs during the year and not require irrigation like turf grasses need.
Incorporation of native grasses may require the use of tractors that drill grass seed into the desired areas to the appropriate depth. Covering this seed with straw will help the soil retain moisture that will be used later for germination. The straw also helps the seed from blowing away. It’s important to keep off of these areas as they can be fragile and need time to germinate. Once native grasses emerge and are established on the surface, their maintenance is significantly reduced compared to those planted with turf grass.
Answered by James Hartsig, Duraroot