
Wrong!
First, let’s put aside the discussion about whether aerating turf really is really necessary… and, depending on your type of soil, it’s more often a waste of time than useful. (Hint: aerating a lawn is only effective if the soil is very dense and hard, probably clay, and even then, must be followed by topdressing with compost or a much lighter soil if you expect to change anything.)
Here, however, let’s just assume that your lawn really would benefit from a good aeration. If so, can a simple sandal replace a mechanical aerator?
Not a chance!
It Punches Without Aerating
Remember that a mechanical lawn aerator works by removing cores of soil. This leaves holes that air can penetrate so as to reach the roots of the lawn grass. An aerating sandal doesn’t remove soil cores: it only punches holes the ground, thus compacting the soil even further. The holes it makes pack the soil particles even more densely than before, leaving a smooth and impermeable perimeter. Thus they reduce air circulation to the roots.
Okay, there are now holes in the soil that contain a bit of air, but the roots can’t take advantage of them, compressed as they are by an overly dense soil.
Also, the damage caused to lawn grasses (which are living plants, after all) by punching multiple holes—thus perforating their roots, tearing into their crown and chopping up their rhizomes—can be considerable and the lawn will take a long time to recover from the wounds. (This is one of the reasons why lawn aeration remains a technique of questionable utility.)
Not So Easy to Use
Essentially, aerating sandals are totally useless, something you’d do best to sell off a garage sale with all the other ineffective items that you’ve accumulated over the years. I recommend saving your lawn-care budget for something that really can help your lawn grow better!
