Grass Seed & Freezing Temperatures

While you should plant cool-season grasses in the early fall or spring, you could plant them during the winter and still have some potential for success. But you need to understand that by doing so you risk the seeds rotting, not germinating, or even dying after germination due to freezing temperatures.

The colder climates in the United States are labeled Zone 1 geographically, according to Landscape-America.com, and they can experience freezing temperatures during the winter months. But that needn't stop you from planting your grass seeds, particularly if you take the proper steps to ensure their success.

Zone 1 includes all of the upper half of the country, as well as some lower elevations in Kansas, Virginia, Kentucky, North Carolina,Tennessee, southern Ohio, Arkansas, Indiana, Missouri and Illinois, which also serve as transitional turf between the colder states in the North and the warmer states in the South.

The four grass types most favorable for planting in Zone 1, where freezing temperatures are likely to occur, are Kentucky bluegrass, perennial ryegrass, red fescue and turf-type tall fescue. And while each grass seed type can be sown during freezing temperatures, poor germination or overall lawn grass failure may result.

Of the cool season grasses suitable for Zone 1, Kentucky bluegrass is the most commonly used. This grass is a high-quality lawn grass. Northeastern and northwestern states in Zone 1 favor perennial ryegrass, which germinates quickly and adapts better to cooler, moister environments than the other three types. However, this type of grass typically lasts for only one season.

Red fescue grass seed should be sown in Zone 1 spots that are shadier or cooler than others, as this grass seed does better in those conditions. The last grass seed type for the colder parts of the country is turf-type tall fescue, which is the most disease-resistant of the four, according to Landscape-America.com.

All four of the cool-season grasses can actually be planted on top of snow, according to Grassing.com. As the ground freezes due to low temperatures, cracks form in it. Later, when the snow begins to melt, your grass seeds will move downward into the soil and also into those cracks. There is a greater failure rate for this type of cold weather planting, but it can be done with some potential for success.

If you plant your grass seed too closely to the time when freezing temperatures are likely to occur, it might not germinate well--or at all. The seeds also can rot due to the excessive cold temperature or moisture of the soil. In addition, germination could occur but the seed could later die if temperatures drop after germination.