How do I Overseed Fall Fescue?

Overseed fall fescue in September.

Maintain lush fescue lawns with annual overseeding designed to ensure continued growth and thick establishment. September is the ideal month for overseeding fall fescue lawns, as the danger of heat damage to seeds has subsided. With the right tools and attention to proper soil preparation, successful overseeding will result in a turf that grows stronger every season.

Difficulty:

Moderately Easy

Instructions

Things You'll Need

• Motorized or pull-behind core aerator
• Power rake (or handheld for smaller areas)
• Broadcast spreader (or handheld rotary spreader for smaller lawns)
• Hose
• Spray nozzle

Preparing the Soil

1. Know a lawn's square footage before overseeding. large home image by Cindy Haggerty from Fotolia.com

   Determine square footage of lawn space to ensure adequate seed coverage. Calculate square footage beginning with the original lot size indicated in the land plan. Subtract the square footage of the house, garage, deck, driveway garden, pool or any walkways. The remaining square footage determines the amount of seed needed for overseeding fall fescue. According to an article by Kathleen Howard for Kansas State Research and Extension News, the overseeding rate for existing lawns with tall fescue or Kentucky bluegrass is half or less of what's recommended for starting a new lawn from scratch. For news lawns, Kansas State recommends the full-seeding rate of 6 to 8 lbs. per 1,000 square feet.

2. Compacted soil requires aeration before overseeding. bench image by Mirek Hejnicki from Fotolia.com

   Aerate the lawn to loosen compacted soil and break up thatch. Motorized aerators are available for rent at home improvement centers. The aeration process breaks up compacted soil to promote seed germination and healthy lawn establishment. According to the landscape professionals at the Lawn Care Academy, the removal of soil plugs during aeration not only relieves soil compaction, but also increases gas exchange and water availability to the roots. Aerate in even rows (like mowing the lawn) to extract small, cylindrical-shaped 2-inch plugs of dirt from the ground. Break up any remaining thatch or large dirt clumps with a garden rake or power rake to ensure optimal seed contact with soil.

3. Remove debris and thatch before overseeding fall fescue. Lawn Clippings image by Towards Ithaca from Fotolia.com

   Rid the area of any remaining thatch, sticks or debris that may inhibit seeds from establishing contact for germination. Dispose of unwanted thatch in lawn refuse bags or composting pile to avoid reseeding of any weeds. Rake the area to an even surface to optimize the ease of pushing a broadcast spreader.

Overseeding

1. For broadcasting grass seed, walk in straight rows as in lawn cutting. she's mowing the lawn image by mavrick from Fotolia.com

   Load the broadcast spreader with seed according to instructions on fescue bag and spreader. Spread seed according to indicated settings on bag to avoid heavy seeding that results in overcrowding, thereby canceling out of seed germination. According to the experts at the Lawn Care Academy, walking the spreader in straight lines ensures even seed coverage. Avoid swerving, which results in missed areas and uneven seed germination.

2. Check the broadcast spreader's seed distribution between passes to make sure seed is being dispersed equally to all areas. Increase the opening in the hopper of the spreader as needed to avoid clogging. Walk faster when the opening is wider, to ensure consistent amounts of seed are disbursed through spreader.

3. Keep the soil profile moist. grass image by timur1970 from Fotolia.com

   Attach a spray nozzle to the hose and lightly sprinkle seeds a few times a day to promote rapid germination within five to ten days. Moisten seeds evenly to avoid puddles. According to Clint Waltz and Gil Landry, Extension Turfgrass Specialists at the University of Georgia, daily watering of 1/8 inch to 1/4 inch is necessary for the first few weeks. Water less frequently as seedlings begin to grow, but make sure the soil profile remains moist during seed establishment.

Tips & Warnings

• Hire a helping hand if necessary and seek the advice of home improvement specialists to determine the extent of aeration equipment needed for a particular lawn.

• Wait until after a hard rain to aerate the lawn. Doing so makes aeration easier and more effective in hard soil conditions.

• Seeds germinate faster in well-aerated soil.

• Approach motorized lawn aerators with caution as they are heavy and can be hard to operate.

• Avoid spreading too much fescue seed. Seeds can't germinate when they are competing for establishment.

• Avoid overseeding before September, as seeds will dry out and burn in hot conditions.

• Resist the urge to over-water young seedlings; they will die if they are consistently surrounded by puddles of water.

References

• Savvy Gardner: Overseeding A Lawn
• Fescue: When to Plant Fescue Grass Seed
• Kansas State University: Overseeding in the Fall Can Repair, Improve Lawn
• Georgia Center for Urban Agriculture: Seeding Tall Fescue Lawns
• Lawn Care Academy: Techniques For Overseeding Lawn

Resources

• Lawn Care Academy: Techniques for Overseeding Lawn