Anyone who has aerated their lawn in the past knows that you shouldn’t mow immediately afterward. It’s important not to mow right after aerating for a couple of reasons, and I recommend that you wait for a minimum of one week after aerating your lawn. In this article I’ll answer the question “Can I mow after aerating my lawn?” and explain why it’s not a great idea to do so.
The main reason why you should not mow your lawn immediately after core aeration is that you are much better off mowing before you aerate.
Another reason why you shouldn’t mow a freshly aerated lawn is that it’s the best time to do your overseeding and fertilization (allowing that seed and fertilize to drop into those new holes.
But let’s stop and talk a little more about aeration and what best practices are.
What is Aeration?
Lawn aeration is a process in which you create holes in the soil that allow more oxygen and water to penetrate your turf.
I consider aerating your lawn to be essential if you want the healthiest and most beautiful lawn possible and there’s usually no better return on investment than renting an aerator for a day.
Lawns that are improperly aerated will get very compacted. Compact soil will mean that your lawn doesn’t get enough oxygen from the air and water, as well as essential nutrients.
When you aerate, you loosen the soil. This gives your grass roots the chance to establish more strongly and grass (especially rhizome grass) spread as they should.
How to Tell if Your Turf Needs Aerating
Lawns become compacted quite quickly when people frequently walk on them. Once your soil begins to become compacted, less and less oxygen gets into the soil and the toxic gases that the soil has to release cannot get out.
Lawns with compacted soil never have a healthy or attractive appearance.
The worse the compaction, the less attractive the lawn will look.
Another problem with compacted soil is that it will be more likely to suffer from problems with disease and pests.
It will also have difficulty dealing with environmental stresses.
Aeration helps to slow down thatch build-up and delay the need to dethatch your lawn.
Thatch builds up on your lawn when dead plant material is left to sit. When the layer of thatch gets to be more than an inch thick, it will be difficult for new grass roots to penetrate the soil. Excessive thatch will also make your lawn more likely to have problems with pest infestation and disease.
When Should You Aerate?
Fall is generally the best time of year to aerate because it’s the best time to overseed your lawn.
If your lawn is having problems with heat stress, then you can aerate in the summer.
Spring can work, but you have to get the timing right. Early spring aeration can be just as good as fall aeration if you overseed early enough (once the soil comes to temperature).
You should water your lawn before you aerate it (or do it the day after a heavy rain). In general, aeration creates the most benefit on soil that is a little bit moist.
Then, try not to mow right after aerating. Instead, mow beforehand, and consider laying seed and fertilizer over your lawn after aeration and give your lawn time for that new seed to germinate before you mow again.
What Equipment Do You Need for Aeration?
There are different kinds of equipment that can be used for aeration.
Core or plug aerators are generally believed to be the best (I’m a believer). A core or plug aerator will have hollow tines, arranged in rows. These will remove plugs of soil from your lawn and then put them back on top of the grass.
Some people wonder if they should mulch mow these core aeration plugs to help them break down quickly. I don’t recommend that. Given time, these plugs will break down and add nutrients to the soil on their own schedule.
If you mow and chop those plugs up with your mower, that soil will drop right back into your aeration holes and fill them in. That’s not really what you want.
The Three Types of Aerators
There are three main methods of mechanical lawn aeration. These are:
While core or plug aerators are usually considered the best type of aeration equipment by the professionals, there are some other kinds out there that some people use.
These are spike and slicing aerators.
Slicing aerators are equipped with rotating blades. These blades slice or cut through the grass, as well as any thatch. They penetrate into the soil.
Rather similar to the spike aerator, a slicing aerator doesn’t take any soil from the ground. They do, however, leave areas where water, air, and nutrients can get into the soil more easily than otherwise.
The spike aerator is the most basic type and can cause problems if used over a larger section of lawn. With spike aeration, the only process is creating a hole in the soil. A tine in the shape of a spike that is solid is used.
The most basic iteration of this is the spiked aerator sandals that a few homeowners will wear when doing their work in the garden. The problem with spike aeration is that, if used over a larger area, it tends to make compaction even worse.
The soil will become even more severely compacted together in the area where the hole is made since the soil is just being smushed down.
Finally, you may have heard of liquid lawn aerating products, which you spray on the lawn (and sound too good to be true). I tested and reviewed Aerify Plus to see if liquid aeration works on lawns, and you may enjoy that article with before and after photos if you’d like to learn more about the pros and cons of that method.
You Shouldn’t Mow After Aerating My Lawn
You can mow after using a slicing or spike aerator. But when you core aerate your lawn mow beforehand and then, give it a week or more before you mow again.
When to Aerate and Why?
Remember, you should do your lawn aeration when your grass is in the stage of active growth.
This is because your grass will recover more quickly and be able to fill in the parts of the lawn where the aerator has exposed soil.
I never recommend trying to aerate a dormant lawn.
If you have a cool-season grass (which you likely do if you live in a northern area), the best time of year to do your aeration is usually early fall or spring. If you live somewhere more southern and have a warm-season grass, the general rule is that you should aerate in the late spring or early summer.