There are several steps you need to take to prepare your lawn for aeration and overseeding. First, test and fix the soil as necessary. Then, clear, mow, and dethatch the lawn, identify the most compacted areas, mark obstacles, water the lawn, rent or buy an aerator, and gather materials for overseeding.
How to get your lawn ready for aeration and overseeding
If you think all you need to do to get a healthy, thick lawn is simply throw down some grass seed and water it, you’re wrong. For the best results, there are several things you need to do before you aerate and overseed:
Test and amend the soil
Test your soil to find its nutrient and pH levels. Healthy soil is key for seed germination and growth, so use the soil test report to determine whether you need to add any soil amendments in preparation for aeration and overseeding.
For example, you may have to apply lime to correct acidic soil or sulfur to fix alkaline soil. Grass likes a neutral soil pH (level 7), so you won’t see healthy growth if your soil is outside that range.
You can add a starter fertilizer right after overseeding to help the new grass germinate faster, develop strong roots, and grow into a thick, lush lawn.
Tools: Soil testing kit (if done at home), fertilizer, fertilizer spreader, gloves, dust mask, garden rake
Pro tip: You can also send soil samples out for testing at your local extension office.
Clear the lawn
In preparation for aeration and overseeding, clear the lawn of any obstacles. This will allow the aerator to reach the entire lawn and create space for even overseeding.
Remove any of the following from your yard:
- Outdoor furniture
- Kids’ toys and other play items, such as trampolines
- Garden tools
- Pet items
- Bird baths
- Statues
- Other hardscaping items that you can temporarily relocate
Tools: Work gloves, storage bins or bags, cart or wheelbarrow for moving heavier items, covers if you’re storing items outside, a tarp for piling up various items and moving them
Mow the lawn
A day or two before aeration and overseeding, mow your lawn shorter than the recommended height for your grass type. Stick to the one-third rule (never remove more than one-third of your grass blades), but aim for the lower end of the recommended range. An ideal shorter height is 1 to 1 ½ inches (without scalping the grass).
Shorter grass helps in the following ways:
- It makes it easier to see areas needing extra attention.
- It helps the aerator penetrate the soil and improves seed-to-soil contact when you overseed.
- It exposes the soil to more sunlight and air, helping the seeds germinate and thrive.
- It reduces competition from existing grass to allow the new seedlings to grow.
When you’re done mowing, compost the grass clippings or rake, bag, and dispose of them responsibly. This creates a clean canvas for dethatching, aerating, and overseeding.
Tools: Lawn mower
Dethatch the lawn
When preparing for aeration and overseeding, dethatching is an essential step: It clears away dead grass and organic matter that builds up between the soil surface and grass blades and removes debris.
Measure the thickness of the thatch layer with a ruler. If it’s more than ½ inch thick, it can prevent proper aeration. The aerating tools won’t be able to reach the soil and it can block proper seed-to-soil contact when you overseed.
Once you’re done, rake the lawn to loosen the top layer of soil so when overseeding the seeds can nestle into the soil later on.
Tools: Leaf rake, leaf blower, dethatcher
Identify the most compacted areas
Walk around your lawn and identify areas with heavily compacted soil. Causes of compacted soil include heavy foot traffic, overwatering, and soil type.
To better identify areas, try:
- Visual checks: Look for areas where your grass isn’t thriving. Besides issues such as diseases, pests, nutrient deficiencies, or insufficient irrigation, compaction can also cause bare patches and yellowing.
- Soil penetration test: Take a screwdriver or garden spade and push it into the soil. If the tool only penetrates the soil 1 or 2 inches or not at all, your soil is compacted.
- Water penetration test: Pour some water on a few spots in your yard. If it pools or takes a long time to seep into the soil, it’s a sign of compaction.
These problem spots may need extra passes with the aerator to break up the soil. Mark them with flags for good visibility.
Tools: Marker flags, screwdriver, garden spade, watering can
Mark obstacles
To avoid damage to various objects in your yard, identify and mark them before aerating. These can include:
- Sprinkler heads and irrigation lines
- Cable wires
- Electrical lines
- Gas lines
- Invisible dog fences
- Lighting
- Hoses
Aerators can easily puncture anything buried 2 to 4 inches in the ground (some even 6 inches), leading to costly repairs or safety hazards.
Tools: Marker flags, lawn-safe spray paint, measuring tape for identifying distances, a map or diagram of your yard
Water the lawn
Based on your sprinkler output, which you can figure out by taking the tuna can test, give your lawn about 1 inch of water before aerating and overseeding. In case of rainfall, skip this step.
Soft, moist soil is easier to aerate, allowing the tools to penetrate deeper to pull plugs. Plus, it helps grass seeds settle and germinate faster. Avoid aerating overly wet soil (such as after heavy rainfall), as it can cause clumping and damage to the machine. The holes also may collapse right away, as the wet soil won’t be able to hold the shapes.
After overseeding, your watering schedule will need to change as follows:
- After spreading the seed, water the area thoroughly but lightly to help the seeds settle and jumpstart the germination process.
- In the next 10 to 14 days, water lightly 1 to 2 times daily to maintain the top inch of soil moist (not soaked). After watering, gently press your finger into the soil; if you can easily press down 1 inch and feel moisture, your soil has enough water. Use a gentle spray to avoid disrupting the seeds.
- Once the seeds germinate and show growth, water less frequently but more deeply. For the next few weeks, water once every few days and aim for a soil moisture depth of about 2 inches.
- After this period, you can shift to your normal watering schedule. Water your lawn as usual, depending on your grass type, soil type, and climate.
Tools: Garden hose or sprinkler system, tuna cans, timer, ruler or measuring tape, notepad if you want to record your findings
Rent or buy an aerator (for DIYers)
If you’ve hired a lawn care pro to aerate and overseed your lawn, you can skip the next steps. You’ve done everything to prepare your lawn.
If you’re aerating yourself, you’ll need an aerator (which you can rent or buy for the job) or a liquid aeration product:
- Core aerators: Also considered the most effective, they remove small cores of soil to allow air, water, and nutrient penetration.
- Spike aerators: Push down on the soil to make holes, but this can make compaction worse over time.
- Liquid aeration products: Liquid aeration blends are poured into a hose-end or backpack sprayer to apply to the lawn.
Pro tip: If your lawn is large, invest in or rent a power aerator to minimize time and effort. For smaller areas, manual aerators are usually enough. Both spike and core aerators have these two options.
Gather what you need to overseed (for DIYers)
To successfully overseed a lawn, you’ll need a few tools and supplies in your repertoire:
- High-quality grass suited to your climate and existing lawn (whether cool-season or warm-season).
- A seed spreader such as a broadcast spreader, drop spreader, or handheld spreader. The type depends on your lawn size and needs. Broadcast spreaders are typically best for larger areas and even coverage, while drop spreaders and handheld spreaders target specific areas, such as edges and tight spots.
- A lawn roller (optional) to help you press the seeds into the soil better.
FAQ about how to get your lawn ready for aeration and overseeding
How do I know if my lawn needs aeration and overseeding?
If your soil is compacted or your lawn has bare patches and thinning grass, it will need aeration and overseeding. These practices reduce compaction and improve grass thickness and health.
Can I skip aeration and just overseed if my soil isn’t compacted?
Yes, if your soil is loose and drains well, you can skip aeration and just overseed. But aeration usually improves seed-to-soil contact, which will help your grass germinate successfully.
Should I overseed the entire lawn or just bare areas?
Ideally, you should overseed the entire lawn for even thickness, but you can also focus on bare spots if the rest of your lawn looks lush and healthy.
Expert help is always available
Preparing your lawn for aeration and overseeding is essential if you want a lush, healthy yard. But if you’re managing a busy schedule, are a lawn care newbie, or simply want to leave it to the experts, you’re in luck.
Lawn Love can connect you with a local lawn care professional who offers both aeration and seeding services. That way, you’ll have peace of mind, a vibrant lawn, and more time for yourself and your family.
Sources
Main Image Credits:
Aeration: Dziurek | Adobe Stock | License
Overseeding: Shutterstock
