When is the best time of year to plant grass?

Grass Planting in Ann Arbor, MI

Newly Sprouted Grass Seedlings

     If there is an area in your yard that needs grass seed planted, you might be wondering when the best time to put seed down is. In Michigan and the rest of the Midwest, seed can be planted from April through October. However, for a variety of reasons, the month of September is ideal.
     The turf grasses used in Michigan are cool season grasses. Common types include Kentucky Bluegrass, rye and fescue. These grasses germinate best when day time temperatures are between 60 and 75 degrees Fahrenheit, which typically happens by the second half of September. Ideal temperatures mean quicker germination and the sooner the grass fills in, the less time weeds have to take over. Although grass planted at the end of October will sprout, a hard frost when seedlings are small can have a negative effect. By planting in September the grass will have time to become established before it goes dormant for the winter. 
     Another benefit to planting in September over April of May is that there are less weed seeds for the grass to compete with. In the spring, the temperatures are right, but many weed seeds can be lying dormant from the year before. Most weeds sprout at higher temperatures than the previously stated grasses but far before the turf would have completely filled in. Because of this, a spring planted lawn will usually end up with more weeds than one started in the fall.
     Lastly, with fall comes more frequent rain than in the summer. Soil moisture is needed for about one week to get ryes and fescues to sprout and up to a month for bluegrass. After seeds sprout, watering is still needed on a regular basis for a few weeks. The rainy season means less time is spent watering with a hose or sprinklers, saving time and money. 
     If time is of the essence, you can get grass to grow from spring through fall. If you want a nice, full lawn without weeds, September is the time to do it. Not only will the final product be superior, but it will take less work. Next spring when others are starting their grass planting projects, your lawn will already be alive and thriving.  

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