KC Gardens

If you’ve planted grass seed, here’s how to nurture it through fall and winter

Freshly planted grass seed must be tended through the fall and winter.
Freshly planted grass seed must be tended through the fall and winter. Kansas State University Research and Extension

Summer’s unpredictable conditions have taken a toll on many lawns.

Uneven moisture and high temperatures resulted in dead patches. Many of us planted grass seed in hopes of reviving that lush green carpet. Now that the seed has germinated, here is your checklist to ensure success in your lawn come spring.

Keep up the water

Frequent applications of water is a must for germination to take hold.

There is no clear answer for when and how much water to apply because it is dependent on the weather patterns. Warmer, sunnier fall days will call for more water, while cool, cloudy days require less. The purpose of keeping the seeds moist is to force the developing roots deeper into the soil.

Apply water when the grass shows signs of stress. The goal is to return to the typical deeper and less frequent applications of water.

Make sure the grass has ample moisture during winter if it turns out to be another dry, snowless season. Water the lawn on a warmer winter day to safeguard against winterkill.

Mowing is required

Newly established grass needs to be mowed on a regular schedule. It is recommended to keep grass length at three inches. Mowing shorter than three inches stresses the grass, removes the green growth and limits the crown growth, resulting in the inability to fill the dead areas.

Mowing the lawn and occasionally walking on it will not harm the tender blades.

Don’t skimp on fertilizer

Germinating grass is hungry and watering it leaches fertilizer from the shallow root zone. A starter fertilizer is usually applied at seeding. About four weeks after germination, apply a follow-up application of high nitrogen fertilizer to keep the seedlings growing.

Examples of high nitrogen sources are 30-0-0, 27-3-3 or 29-3-4. The nitrogen speeds up the establishment of the seed, builds a strong root system and encourages crown growth. It is the spreading of the crown that leads to a thick, dense lawn.

Depending on the timing one last fall application of high nitrogen can be applied before Thanksgiving to send the grass into a winter slumber fat and happy. Just be sure the applications are about a month apart.

Keep leaves off

Leaves will soon change color and start to fall. If they are not picked up, the new grass will die over the winter from lack of sunlight. If you stay on top of the drop, they can be picked up when mowing or raking.

Overseeding a lawn is work and just the first step in repairing summer burnout. These falls tasks will ensure that come spring, your tired summer lawn will be a carpet of spring green.

Dennis Patton is a horticulture agent with Kansas State University Research and Extension. Got a question for him or other university extension experts? Email them to garden.help@jocogov.org.