Revitalize your lawn a weekend using just one or two tools. An aerator helps the soil breathe and a power rake gets it ready for seeding.
Lawn looking thin, bare or brown? You can revitalize it in a weekend using just one or two tools from a local rental or garden center. The power core aerator (Photos 1 and 2) loosens any compacted soil in your yard and breaks up thatch. Thatch is a cushion of old, partially decayed grass roots and stems that develop in many sodded lawns (Figure A). It separates the actively growing crown of the grass plant from the soil surface.
The power rake (Photo 3) is equipped with vertical fixed tines to cut the soil and prepare a thinned-out lawn for reseeding.
For you Northern homeowners whose lawns experience a hard freezing winter, the first dew in August is your signal that it's time to aerate to ensure lush grass next spring. For homeowners in warmer or more arid states, aerate your lawn next spring to boost those warm-climate grass varieties before they go dormant in mid-summer.
Power aerators and power rakes can usually be rented by the hour, half day or day. Because these two machines are in high demand (especially on weekends), ensure that your work plan will flow uninterrupted by reserving both machines in advance. Save some money by first renting the aerator, then picking up the power rake when you drop off the aerator. Rejuvenate your lawn using these strategies:
If you've never used an aerator or a power rake, practice on an isolated section of your yard. The first time I used a power core aerator, it nearly dragged me off the lawn and into the street. My uncle still enjoys recounting that story.
The zone where grass meets soil is an amazing micro world of plant roots, bacteria, insects and complex chemical reactions. Healthy soil is soil that's loose enough to allow air, water and nutrients to pass into it to foster plant growth. Keep these concepts in mind:
Compacted soil strangles roots
The causes are many: In existing lawns, the top 1 to 1-1/2 in. of soil becomes compacted over time from foot traffic, riding lawn mowers, high clay content and rain. New lawns often have problems—beginning with home construction or remodeling—when topsoil is bulldozed, remixed with subsoil and over-compacted. Sod lawns that are hastily laid over unevenly graded lots look good enough for the contractors to get paid, but they can manifest problems after one or two growing seasons. In both cases, the eventual outcome is choked and starved grass roots.
Too much thatch chokes the lawn
Thatch is a tightly woven layer of partially decomposed grass roots and stems that can develop over several years in the zone between the crown of the grass and the soil surface. Contrary to myth, grass clippings don't contribute to thatch buildup, and power raking doesn't cure it. Thatch becomes a problem when it's thicker than 1/4 in. It's a sign that lawns have been over-watered at night, damaged by drought, over-fertilized with high nitrogen fertilizer or that the soil is too alkaline. Thatch occurs most often in new lawns when sod is installed over dips and voids in the regraded yard or in poor or improperly prepared soil and is then incorrectly watered. Break down excess thatch by using a rotary spreader loaded with thatch decomposter mix on the lawn (Photo 5).
You can reverse the damage
Revitalize compacted soils once a year. Run a power core aerator over the lawn to pull up plugs of dirt, creating voids in the subterranean soil to provide space for and stimulate new root growth (Figure A). The slashing action of the power rake's vertical tines slits the soil's surface where seed, nutrients and water can combine to regenerate the lawn.
America is serious about growing grass. Since the mid-'90s, the total acreage of lawns (homes, golf courses, businesses, etc.) has exceeded the amount of land used for agriculture. Soil types and grass varieties differ by climate and region. Learn more about your soils, grass varieties and recommended lawn care practices by talking with experts at garden centers or a county extension agent. For a more complete lawn assessment, take along two 4 x 4 x 4-in. lawn samples cut from the best and worst areas of your yard. The best time to aerate and reseed cool-season grasses (varieties like Kentucky bluegrass and perennial ryegrass) is four weeks before the trees lose their leaves in your area. The best time to rejuvenate warm-season grasses (varieties like zoysia grass, bermuda grass, tall fescue and St. Augustine) is late spring. If you follow this plan, you'll give your grass time to germinate, grow and recover from the aeration process before it goes dormant. You'll also be able to establish a fuller, thicker lawn to help keep next season's weed growth to a minimum.
Make two passes across the lawn perpendicular to each other with a power core aerator so that the aeration holes are spaced 2 to 3 in. apart. Set the spoon penetration by turning the depth control knob to the deepest setting. For operation on hills and uneven terrain, load or remove one or both onboard weights to increase stability.
Run the aerator in the morning when the turf is cool and moist (but not soggy). You want the aerator's hollow spoons to easily penetrate 1-3/4 in. to 2-1/4 in. into the soil and pull out full-length dirt plugs. If a large, straight-slot screwdriver can't easily penetrate 3 to 4 in. into the soil, the soil is too dry. The day before aerating, water the soil till it passes the screwdriver test. Mow your lawn just before watering and aerating it.
Most lawns, whether seeded or sodded, are planted over a fairly skimpy layer of topsoil. Over time, lawn mowers, pets and pick-up football games compact the soil, making it difficult for air, water and vital nutrients to penetrate to the grass roots. Your challenge: to restore healthy soil conditions that nurture your lawn. To loosen and aerate the soil, rent a power core aerator (Photo 1). They're available at rental centers, plus some hardware stores and garden centers.
In our area, an aerator rents for about $20 per hour. This self-propelled lawn machine employs a row of evenly spaced, hollow, 3/4-in.-dia. spoons that penetrate the soil up to 3 in. deep. They pull out soil plugs, leaving a pattern of holes in the lawn that will readily absorb water, air and nutrients (Photo 1). Our rental power core aerator may differ from what you'll rent, but they all work basically the same. Ask your rental center to demonstrate the machine's controls and the procedures for turning and reversing, then follow these general guidelines:
Prepare soil for reseeding using a power rake. Its solid tines (see close-up photo) slash through any thatch mat and score the surface of the soil. Power-rake only after aeration and in the afternoon, after the morning dew has dried—so the dead grass and roots lift out loosely without clumping. Make two opposing passes with the power rake, each 45 degrees across the pattern used by the power aerator.
Rotating tines pull up lawn thatch to the surface
Between passes with the power rake, always use a hand rake to loosen dead grass and lawn debris to ensure that new seed or fertilizer will contact the soil. If you reseed your lawn, make two passes with a rotary spreader. Each pass should contain half the recommended lawn seed for your square footage of lawn. Run it after each time you hand-rake in the same direction the power rake slit the soil so more seed can drop into the core holes and slits without being raked off.
Feed the soil and accelerate thatch breakdown with a rotary spreader loaded with thatch decomposter mix. We set our spreader at No. 15-16 to broadcast the decomposter mix at a rate to cover 2,000 sq. ft. of yard. If you've reseeded your lawn, apply decomposter mix and a 9-13-7 new lawn fertilizer that contains slow-release nitrogen. After reseeding, water the lawn twice on that first day, 1/4 in. each time.
Often, older lawns that haven't been aerated and maintained have turf that's scraggly and thin. After power aerating the lawn, your first step to correct this problem is to rent a power rake—a gas-powered lawn machine that's roughly the size of a lawn mower but 1-1/2 times heavier (Photo 3). They're available at rental centers for about $15 an hour. The power rake is much less complex than a core aerator and easier to operate. Ours wasn't self-propelled; we pushed it around the yard. It should be operated at full throttle to maximize the power of the continuously spinning, solid, vertical tines (see Photo 3, inset) that pull dead grass and lawn debris up to the lawn surface, and leave a pattern of 1/4-in. deep slits in the soil surface. Used after the aerator, the power rake will prepare the soil to receive seed and/or fertilizer. Follow these tips for using a power rake: