Lawn Aeration and Overseeding: Frequently Asked Questions
Updated: Aug 29, 2019
What is Core Aeration for Your Lawn?
The key to a beautiful lawn is a strong root system, and the best way to get there is by regular Core Aeration and Overseeding. Keeping your lawn looking lush and green all year is a demanding task. Most grass types aren’t native to the Mid-Atlantic United States, so keeping your lawn thriving through our humid summers and icy winters is a battle against nature. Read on to find out how your lawn will thrive with regular Aeration and Overseeding.
Core Aeration is a type of lawn aeration that creates holes throughout your lawn by pulling up small soil plugs (called “cores”) and thatch (the layer of dead turf grass on top of the soil). This can be done manually or with a special machine called a core aerator. For the best core depth (~3 inches long) aerate your lawn after watering or recent rainfall, since dry soil is more difficult to break through. Removing these cores at regular intervals relieves soil compaction, which instantly increases water availability and gas exchange for the root system.
Core Aeration (or plug aeration) is slightly different than spike aeration. Spike aerators will force holes into the lawn, but they do not remove the soil plugs. While this can help moisture reach the roots, it typically INCREASES soil compaction, which can further compound your problems long term.
The process of Core Aeration will leave the cores (soil plugs) spread across the surface of your lawn. Don’t worry about removing these! Over the next one to three weeks, they will break down naturally, filtering back into the holes from the aeration machine. Mowing your lawn will also help break up the plugs and integrate them back into the soil.
The result? Now that more oxygen, water, and nutrients can penetrate deep into the soil and down to the root zone, new and deeper roots will begin to form. In around 35-45 days you’ll begin to see sprouts as new grass growth that will continue through the season.
What is Overseeding?
Overseeding is the process of planting new grass seed onto your existing turf; the process is a simple “hack” that golf course managers have long since used to keep their turf in top condition.
Overseeding has the most benefits for lawns with thinning grass, disease, and invasive species, as it will introduce new grass types that build disease resistance and counteract the growth of weeds. Homeowners with “cool season” type grasses that are best suited for a mid-Atlantic hardiness zone (i.e. species such as tall fescue, fine fescue, perennial and annual ryegrass and bluegrass) will stand to benefit the most.
Should You Aerate and Overseed your lawn?
Most home lawns that look less than ideal are suffering from a buildup up of compacted soil and thatch.
Compacted soil – If your lawn is heavily trafficked, or has a high clay content (like most soil found in the Mid-Atlantic states), it’s more likely to become compacted, which decreases the amount of oxygen the roots can access. You can perform a simple test by squeezing a clump of soil in your hand. If it compresses rather than crumbling, your soil has more clay than sand, and likely needs regular aeration to remain healthy.
Lawn thatch is the layer of dead stems, leaves, and roots that sits directly atop your soil. These are generally the tougher components of grass that won’t decompose as easily as the grass blades. Keeping up to a half-inch layer of thatch on your lawn is fine because it provides a protective layer for the roots. But when the thatch layer gets heavier, it begins to smother the roots, blocking much-needed air, water, and nutrients from seeping deep down into the root system. Too much thatch also makes your lawn susceptible to disease and insect infestations.
A common question we get from homeowners is, “How do I know when it’s time to aerate and seed my lawn?” Your lawn is probably a good candidate if it fits any of the conditions below:
The lawn tends to gets heavy use from children and/or pets (which contributes to significant soil compaction).
It has a “spongy” feel and dries out easily. This indicates a likely thatch problem. If your thatch layer is higher than a half inch high, it’s time for aeration.
The home is part of a newly constructed property. The topsoil of newly constructed lawns is often stripped, and any of the grass established is typically compacted by traffic from construction workers.
The lawn was established through sod and soil layering. When imported sod is used, finely textured soil is often spread over the existing, coarser layer. This layering disrupts drainage, as the finer-textured soil absorbs the water more easily, creating a shallow, poorly-developed root system. Core aeration breaks up the layers and allows the water to reach the roots.
Top Benefits of Core Aeration & Overseeding
To recap, here are the top benefits you’ll achieve after aerating and overseeding your tired-looking lawn:
Eliminate weeds and crabgrass
Loosen and de-compact your soil
Improve root development
Increase water retention
Improve overall lawn health
Fill in the bare spots to create a thicker, greener lawn
When Should You Aerate and Overseed?
For the northern US, the best time for Aeration and Overseeding is late summer and early fall. The onset of cooler, dryer air stimulates growth, and with enough moisture, sunlight, and fertilizer, the seedlings will be well established in time for late fall and winter. Weed competition also becomes less of a factor at this time, so the seedlings have the strongest environment to develop. Spring can be another good time, as the gradual warm up of soil encourages seed germination.
Lawn Aeration: Do It Yourself (DIY) or Hire a Professional?
Simply put, it usually doesn’t make sense for the average homeowner to purchase a high-end mechanical aerator. These machines are expensive and bulky, especially considering you will only be using it sparingly.
Renting a piece of equipment from a local rental center is one option. Keep in mind the transport (most machines are too large to find in a passenger car), and the cost of rental (typically at least $80.00 plus the cost of lawn seed, which will depend on your acreage). The total cost often ends up around even with outsourcing the job.
If you prefer to save yourself considerable time and hassle, hiring a lawn care expert is your best bet. These professionals have all of the latest equipment and will be able to quickly asses your property’s need while referencing years of landscaping experience. They’ll also be able to offer helpful recommendations if they spot invasive species of insects or grass that may lead to a bigger problem in the future. Finally, a professional will use high-quality, natural and organic products that will increase the longevity of your lawn. These products tend to be significantly safer for your family, pets and your neighborhood ecosystem.
Want to learn more about bio-nutritional lawn care? Give us a call to discuss a customized program for your property.