Ah – a good question! And an easy way to answer it is to wait (and you may be waiting some time) for that blink-and-you-miss-it feature on a TV gardening programme when they actually talk about lawns, and….
OK, ranting about the quality of TV lawn advice is not going to help you, but they certainly are partly to blame. You see, I’m talking about aeration – definitely the most misunderstood and badly explained part of routine lawn care. And on those very rare occasions when a TV presenter is asked to mention it, the advice is almost always the same – and it’s wrong.
And yet the whole idea of aeration is so simple! So in this feature I’ll just explain what it is, why we should all do it, and how easy it can be.
First of all – what is aeration and why is it necessary?
Just for a moment compare what we do to our flower and vegetable beds and what we do to our lawn. There’s one huge difference. In the beds we routinely dig over the soil, adding organic matter and generally keeping it in great shape. With our lawns, well – when did you last remove the grass and give the soil a good workout?
It’s simply not possible to look after the sub-lawn soil in the way it needs. And the most damaging result of this is compaction – where the soil is literally squashed and also contracts in warmer weather, squeezing out vital oxygen and water.
So, the next best thing is aeration. By creating narrow vertical channels for the air and rain to reach into the soil, we improve the growing environment for the grass roots and, crucially, increase beneficial microbial activity.
However, this alone isn’t going to reduce the squashed effect in the soil. In fact, use the wrong tool and you make the problem worse – and that is exactly why you will so often be given the wrong advice when you listen to a TV expert.
Use the right tool for the job!
You’ll probably have heard of solid-tine and hollow-tine aeration? Well it’s essential to understand the difference. And this also means understanding why your lawn is not the same as your local sports ground.
If you ask any golf course or stadium how they aerate their turf and you’ll probably be told “with a solid-tine machine”. Unfortunately much of our bad lawn advice is a result of using the same techniques as for sports turf. But no normal gardener can aerate as often and back up those techniques with the intensive year-round care that your local stadium gets.
And that’s why you need a different tool – a hollow-tine aerator.
What’s the difference? Well, as its name suggests, the hollow-tine machine has hollow prongs that drive into the ground; and these remove the soil as plugs or cores. The solid-tine version simply forces its way into the ground; in your garden lawn this further squashes the already compacted soil.
“But can’t I just use my garden fork as they do on the telly?”
No! Not if you want to relive the compaction and promote healthy roots. A solid-pronged tool will help improve air and rain percolation, but it won’t reduce the compaction. The garden fork is a beautiful thing – but use it for digging, not for aerating!
So you have two choices - a hollow-tine fork or a hollow-tine machine. The fork is just like a normal fork but with hollow prongs; but it is hard work! So if you’re covering a large area it really pays to hire a machine – it’s much easier, just like walking up and down with a mower. Save the fork for those tricky corners.
Once you’ve aerated, just brush or rake off the cores (leaving them on the lawn can encourage disease) – but remember they’re full of goodness and can be recycled elsewhere in the garden (or even back into the lawn’s soil as explained in my book, Modern Lawn Care).
So, next time you’re digging over your flower beds….
…spare a thought for the soil that nurtures your lawn. It’s just the same as the stuff you’re digging. But because you can’t give it the same treatment, you have to use aeration to achieve the same benefits. Even just once a year will give you noticeable improvement in the health of your lawn.
For more information about aeration and other really good things you can do for your lawn, get a copy of my book, Modern Lawn Care.