Dormant Seeding of Cool Grasses

Definition

• Dormant seeding of cool-season grasses can mean either seeding when the soil temperature is below 50 degrees F or when the soil is frozen, according to Dr. Bridget Ruemmele, associate professor of turfgrass science at the University of Rhode Island. In either case, the grass seed won’t germinate until soils warm up in the spring. Dormant seeding has risks. If the soil warms up, the seeds could germinate early. Waiting until the ground is frozen increases your chance of success.

Seed Choice

• Dormant seeding can be done with any cool-season grass, but it’s best to choose grass that’s adapted to your local growing conditions, the use of the area that will be seeded and how much maintenance you’re able to provide. The USDA Natural Resources Conservation Service recommends increasing the seeding rate by 25 percent when dormant seeding.

Planting

• Prepare the ground before it freezes by deep tilling, fertilizing and smoothing the surface so it’s firm, but not compacted. Several methods of seeding may be used. You can seed on a frosty morning so the moisture from the melting frost will draw the seed down into the ground for good contact with the soil. You can seed just before a predicted snow, when there’s less chance of the soil thawing or the seed washing away. You can also seed over snow, if it’s not more than 2 inches deep, and if the ground will support your seeding equipment. If you are sowing seeds before the ground is frozen, water the ground so it’s barely damp; don’t saturate the soil. Mulching will help conserve moisture, but don’t use a dark mulch, because it will warm the ground, and your seeds might germinate.

Tips

• Even with proper sowing, your lawn may need some overseeding in the spring, if it looks a little thin in places. This is common, and not a result of dormant seeding failure. Don’t be too quick to assume you need to overseed. Wait and make sure all the seeds have sprouted. Mulching is especially important on sloped areas to keep the seeds from washing away. If the slope of your lawn is more than 3 percent, consider not dormant seeding.