Sowing grass seed in the spring has merit, but sowing in the winter has one or two advantages, too. Freezing temperatures may loosen the soil for you, so that you don't have to till the ground as you would in the spring. Plus, the seeds are already in the ground, and can start sprouting as soon as the weather warms up and conditions permit.
Choose your grass variety. Go with varieties that grow well in cold weather, such as bluegrass.
Watch the weather for the best time to sow your seeds. Try to sow in either early or late winter, when there is little or no snow on the ground.
Till the soil if there is no snow on the ground. This will loosen the top layer of the soil, which gives the seeds more contact with the dirt. If there is snow, you can sow the seeds directly onto the snow.
Spread the seeds uniformly. You can do this by hand, or, for easier and more even sowing, with a lawn spreader. Every square centimetre of soil should receive about 10 seeds.
Lightly sprinkle more soil over the seeds, if there is no snow. If there is snow, leave the seeds uncovered.
Begin watering the seeds well when the weather starts to get warmer, as spring approaches.
Choose your grass variety. Go with one that will stand up to summer temperatures, such as red fescue.
Loosen the soil. If your soil isn't too packed, you can use a rake to loosen it. If your soil is difficult to work with, consider purchasing or renting a tiller.
Spread the seeds uniformly by hand, or with a lawn spreader.
Cover with a thin layer of soil. If you've planted on an incline, you can also add a thin layer of straw to prevent seeds from rolling away, but remove this in spring, when the seeds start to grow.
Begin watering when daily temperatures start reaching 27 degrees C (80F).
Check the weather before planting, to avoid any unseasonable warm spells which could cause the seeds to germinate early.
Sowing grass seed in the winter is very uncertain and the lawn won't start to grow until the spring.