Lawn Pros All Agree This 5-Second Screwdriver Test Is the Simplest, Most Effective Way to See if Your Grass Needs Aerating Right Now
This is the easiest method for checking compaction
Aerating is one of the best ways you can help your lawn in spring. If you wonder how desperate your lawn is for aeration, this quick and simple screwdriver test will reveal whether your ground is compacted and will benefit from this spring lawn job.
When the grass begins to grow as temperatures increase, it's prime time for spring lawn care. Once you understand when and how to aerate a lawn, your grass can put down strong roots, and you’ll have a more resilient lawn.
At the core of this is a five-second lawn screwdriver test that shows when a lawn is compacted. It is a quick test I have used many times over the years, and turf experts all reveal how vital it can be to help you have a strong, healthy, and beautiful lawn. Let’s look at how easy it actually is.
Article continues belowHow to Do the Lawn Screwdriver Test
Spring is the perfect time to aerate a compacted lawn
Many gardeners aerate every spring to make a lawn green and thick so that they can enjoy it every summer. However, not all homeowners are as meticulous with their lawn and may skip a year or two.
This is perfectly OK, but there comes a time when it pays dividends to give their grass some TLC. If your lawn gets a lot of use from children, pets, or family gatherings, then compaction will occur. This can lead to patchy growth and water pooling after rainfall.
To judge when to aerate a lawn, there are a couple of ways to do so. But the lawn screwdriver test is the most straightforward of them all. All you need is a common household tool and a few moments of your time. (And just in case you don't have a screwdriver, you can pick up this great value multi-bit screwdriver from Amazon.)
Mike Goatley, Virginia Cooperative Extension turfgrass specialist, describes the lawn screwdriver test as ‘the simplest, most effective way to assess compaction where most of the turfgrass roots are found’, which is in the top four inches of the soil profile.
The lawn screwdriver test is done after a good period of rainfall, though you can water the lawn in spring beforehand to get the right conditions.
‘Make sure the soil is moist and probe it with a screwdriver,’ explains Mike. ‘If you can push the screwdriver in three inches, you probably do not need to aerate.’
When it comes to what you are looking for, Jason McCausland, Technical Coordinator at Weed Man, adds: ‘If it goes in easily, the soil is loose and healthy. If it’s hard to push, the soil is compacted or too dry.’
Michael Goatley is Virginia Tech's Turfgrass Extension Specialist in the School of Plant and Environmental Sciences. He previously served on the faculty of the Plant and Soil Sciences Department of Mississippi State for 15 years. His current responsibilities include developing turfgrass management outreach programs and research across the state.
Why the Lawn Screwdriver Test Is Crucial
A lawn screwdriver test can help you have healthier grass come summer
Knowing how to check for compaction helps you maintain a healthy, strong lawn. If you wonder why to aerate a lawn, it offers many benefits that help your grass grow vigorously, get the water and nutrients it needs to prosper, and can withstand the rigours of heavy usage and challenging conditions.
Compaction reduces the pore spaces in the soil that hold air and transport water and essential nutrients around the lawn. It also reduces the beneficial activity of microorganisms within the soil. All this combines to leave households with a weaker lawn more susceptible to stress.
Jason McCausland advises: ‘Aerating your lawn in spring improves grass health by relieving soil compaction, allowing air, water, and nutrients to reach the roots more easily. This encourages deeper root growth, better water absorption, reduced thatch build-up, and a stronger, more resilient lawn overall.’
Mike Goatley adds how aerating helps to ‘prevent fertilizer run-off from overly compacted areas’. You should aerate a lawn before fertilizing to ensure it reaches the root zone where it is needed, rather than running off into local water supplies.
Compaction causes issues when homeowners spray weed killer, as the pesticide can run off and damage local biodiversity and get into water sources. Checking a lawn and reducing compaction means you have a nice turf to enjoy, and no damage occurs to the local environment.
You can aerate a lawn with a garden fork, like this Fiskars fiberglass and steel garden fork at Walmart. This is perfect for smaller spaces, but for anything larger, a mechanical aerator, such as this 24-inch rolling lawn aerator at Amazon, can do the job more efficiently than a fork and without the physical exertion.
Jason is a Technical Coordinator at Weed Man. For more than 25 years, he has been an integral member of the Weed Man family and the green industry.
Simple Alternatives to the Lawn Screwdriver Test
Gardeners can aerate a lawn manually with a garden fork
Beyond the lawn screwdriver test, two other easy-to-spot indicators will show when a lawn needs aerating. These are worth knowing to ensure any lawn remains healthy, you avoid bare patches in the grass, or a waterlogged lawn during wet winters.
Jason McCausland says one sign of deep compaction is if the ground feels ‘very hard’ when you walk on it. At the opposite end of the scale, he adds: 'If it's really spongy to walk on, that's an indicator of excessive thatch, and aerating your lawn can help reduce that thatch layer.’
Another crucial lawn care task to remove that layer is to dethatch the lawn in spring.
Spring is also a perfect time to overseed a lawn and combat any thin or bare spots. If you want to fix winter lawn damage and fill in any patches, it is recommended to aerate before seeding. This is because the small holes caused by aerating provide ideal conditions for the seeds to quickly grow stronger roots, compared to being sown on a lawn that hasn’t been aerated.
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Aerating Tools to Shop
This manual lawn aerator features 15 2.8-inch metal spikes. It has a T-bar handle and a metal foot bar to aerate the grass efficiently in spring.
These shoes feature 13 metal spikes, so you can aerate the lawn simply by walking over it. The hook and loop fasteners are easy to secure, and it comes with a tool for removing mud from the sole.
This lightweight rolling aerator has 1.4-inch spikes that will impale the soil as it is pushed over the lawn. It is made of durable galvanized steel and won't rust or corrode.
