Using a trusty garden fork to aerate your lawn is suitable for most gardens.
It’s a nice, gentle workout that you can spread over a couple of weeks, and it leaves no mess of soil plugs like an aerator.
If you have a huge lawn, then it makes sense to invest in an aeration machine, or hire a lawn care company to do it for you.
Fork Aeration Technique:
- Push the fork in about 4-5 inches deep
- Pull the handle back a little, so that turf lifts a tiny bit: don’t yank it
- Repeat every 6 inches across the garden
- Work backwards so you don’t walk on the turf that you just aerated
Pulling the handle back to create heave is essential, don’t just spike the fork down and pull it straight up.
A Verti-Drain Machine for golf courses and sports pitches does exactly the same thing as Andy here, maybe a bit faster:
VIDEO TRANSCRIPT Once you’re scarified your lawn, which can be done in Spring or Autumn, you can aerate your lawn at the same time.
The reason you aerate your lawn is to introduce air and nutrients back into the soil and to break up any pan or any compaction in the soil.
After you have aerated your lawn, you can brush a mix of sand and compost into the holes, or you can just leave the holes as they are.
For small lawns, a normal garden fork will be all right to aerate your lawn.
Just push it in between four or five inches deep and pull back, so the grass lifts a little.
Pull it back out, move back about six inches, and then do exactly the same again.
If you’ve got a very large lawn, you can hire an aerator, a mechanical one, which will do the job.
Just a normal garden fork, that’s all you need, just straight in the ground, kind of lift it up.
After Aerating:
- On rich soil that drains well, you can leave the holes as they are
- To improve the soil, according to what it needs, you can sweep in an appropriate mix of:
- Sharp sand (i.e. not smooth builder’s sand) for drainage
- Compost/manure for fertility
- Leaf mould for water retention
- If the lawn is sparse, scatter grass seeds
- Planting spring-flowering bulbs at the same time as aerating your lawn is a two for one job.
Why Aerate a Lawn?
Lawns, especially on clay soil and any areas that receive high footfall, get compacted, meaning that the soil’s natural structure gets destroyed and crushed into a solid, airless, lifeless mass that won’t absorb water.
Aerating means ‘introduce air into’.
By perforating the soil with your garden fork, you are releasing soil compaction, letting carbon dioxide and oxygen circulate, and water and nutrients reach the lawn’s root zone.
This is where all the soil life is most active, from worms and beetles down to microbes, which can’t thrive in airless, compacted soil.
Soil life is the engine of soil fertility, creating humus and naturally counteracting compression.
What are the Signs of a Lawn that Needs Aerating?
The obvious signs of a compacted lawn that needs aerating are:
- Sparse patches of grass
- Lots of easily visible moss
- Puddles lingering after rainy weather
- Lots of thatch (which is not really dead grass etc lying on the soil, it’s the root mass of the grass piling up on top of the soil: the former tends to be well mixed into the latter, so in practice it’s both)
Heavy clay soils are the most prone to compaction, especially if they are regularly walked on while wet.
But any lawn that sees a lot of use will need aerating.
When Do I Aerate my Lawn?
Aerate your lawn every two to three years in the Spring or Autumn, which is when the grass is growing and the soil life is busy, but not stressed by Summer heat.
You want the soil to be moist and firm, not dry and hard, nor wet, soft and squelchy.
When not to Aerate my Lawn?
You should not aerate your lawn in Winter because the grass isn’t really growing, and also not in a typical Summer because it would dry the lawn out too much.
You might aerate in a wet Summer if your lawn also suffers really poor drainage, but that’s an exception.
Do I need to Scarify My Lawn Before Aerating, or Vice Versa?
You can do it either way, it doesn’t make much difference to the lawn, it’s mostly about your workflow.
With a Garden Fork
A garden fork leaves no mess of soil plugs, so it’s traditional to scarify first, tidy up, then aerate, to avoid walking on the lawn after you aerate.
This way also makes it easier to see problem patches, and if you are sowing seed and/or improving the soil, it leaves the relatively small holes made by the fork nice and open.
With an Aeration Tool or Machine
- The efficient home gardener who simply wants the chore done will usually aerate first, which creates a mess of soil fragments, then scarify over that mess, breaking it all up, then tidy up once at the end.
- A professional gardener who wants to leave a pristine clean finish for the customer will typically scarify first, tidy up all those little bits of dry grass etc (they’ll blow all over the garden in dry windy weather), then aerate over a clean surface, and tidy up a second time.
This is also best when using machines on a neglected lawn with thick thatch, because it lets the machine get snug against the soil without a thatch buffer reducing its penetration depth.
Doing it the second, extra tidy way is a bit better if you are going to seed the lawn and top dress it.
The holes will be nice and clear for the seeds and topdressing to enter, which gives the best germination rate.
However, plenty of gardeners do it the first way, saving time and energy; they sow their seeds and top dress over slightly messy holes, and their germination rate is fine.
For an in depth discussion of the pros and cons of which way round to aerate and scarify:
Should I Buy a Hollow Tine Fork Aerator Tool?
Aerator Tools with special hollow tines are good for seriously compacted lawns, because they remove plugs of soil, which is great when you are improving the soil with sharp sand and/or compost.
However, after you have thoroughly aerated a badly compacted lawn this way once or twice, you will most likely be fine continuing with a garden fork in future.
Borrowing, rather than buying, an Aerator Tool often makes sense, or sharing the cost with a few neighbours.
Unlike a garden fork, it’s a one-job tool, so it’s up to you whether you think it’s worth the cost and shed space.
If you do buy an Aerator Tool, get a high quality one with “side core ejection” AKA “non-clog slots” that spit each plug of soil out the side of the tine, like this Swardman:
A cheap tool with solid tube-shaped tines that spit the plug of soil out the top of the tine is likely to be a right pain to use.
We’ve skipped this Proper DIY video to the part where he explains the poor performance of such a tool:
Can I Aerate my Lawn with a Power Drill?
Yes, you can aerate your lawn really well with a power drill. Just be sure you know where any phone lines or water pipes are…
Obviously, it doesn’t make sense to aerate an entire lawn with a power drill, but it’s a great tool for quickly and thoroughly aerating small problem patches that you want to improve with sharp sand and/or compost.
You can buy wide auger drill bits designed for the job, but using the biggest drill bit for wood or masonry that fits in your drill is fine.
Can I Aerate my Lawn with a Pitch Fork?
Yes, in most cases you can aerate your lawn with a pitchfork. Some will be too weak to lift the soil without damaging the tines, but any sturdy pitchfork should be fine.
Do Aerator Shoes Work?
In our opinion, aerator shoes don’t really work and are not worth buying. According to Rodney, the best way to use them is to “open the bin, insert the aerator shoes, walk away”.
The spikes are too small, and they don’t lift the turf like a garden fork, nor remove a plug of soil like an aeration machine or tool with hollow tines.
This means that the small holes they make squish the rest of the soil together, mildly adding to compaction.
This compaction effect is minor, but still cancels out some of the already small benefit provided by the spikes.