Top-dressing with sand
Why sand belongs on your lawn
Spreading sand on a lawn seems counterintuitive at first, yet top-dressing with sand is one of the most effective lawn care measures, and standard on every golf course. The reason lies in the soil: clay and loam soils compact over time, water drains poorly, and waterlogging and moss follow. Washed quartz sand improves the soil structure for good, because it keeps open the pores and channels through which water and air reach the roots.
Sand develops its full effect in combination with aeration: channels filled with sand remain open drainage paths for years instead of closing again with the next rain. This also helps in the other direction: soils that have become water-repellent after long dry spells take up water again through the sand channels.
And sanding can do even more: pulled across the area as a thin layer, it evens out small bumps caused by frost, moles or use. So the drainage measure becomes a levelling measure at the same time.
Which sand?
Three properties are decisive: washed (no fines that clog the pores again), low in lime (lime shifts the pH and encourages weeds) and the right grain size of 0.5 to 2 mm. Finer sand compacts itself, coarser sand does not work into the turf well. Washed quartz sand of this grain size meets all three conditions. As a quantity, 3 to 5 litres per square metre is a good guideline for the home garden, correspondingly more in the hollows if you are just levelling bumps.
Spreading the sand
The first step is distributing it over the area. Throwing it with a shovel works but is uneven: where there is too much sand, the grass suffocates, and where there is too little, the effect fizzles out. The levelling rake works more evenly and is easier on your back, as it meters the sand and lays it in a defined layer; on larger areas this is the difference between an afternoon project and a quick after-work job.
Levelling rake, drag mat or broom: which to work it in with?
The most common question about top-dressing, and it becomes easy once you distinguish two jobs: levelling and working in. For levelling there is exactly one tool, the levelling rake. For working in there are two that do the same thing: the broom, and the drag mat, which replaces it on the open area.
The levelling rake has a rigid edge. As you pull it across the area, it takes sand from the high spots and deposits it in the hollows: it does not just work the sand in, it levels the area at the same time. That is why it is the tool of choice for uneven areas and for a complete renovation.
The drag mat is flexible and follows the ground. It distributes the sand evenly into the turf and the aeration holes without changing the surface, and it can do more: after overseeding it works the seed in lightly and creates the seed-to-soil contact the seed needs to germinate. On large areas it is the fastest tool for working in.
The broom is the original tool for working in, and it still works: the bristles reliably sweep the sand into the channels, precisely and thoroughly. The drag mat does the same job over a large area in a fraction of the time, which is why it replaces the broom on the open lawn. For touching up individual spots where sand is still lying on top, the broom remains the simplest solution.
Which tool for which situation?
| Your situation | Tool |
|---|---|
| Uneven area, levelling hollows and bumps | Levelling rake |
| Top-dressing a large, level area quickly and evenly | Drag mat |
| Working in new seed and creating seed-to-soil contact | Drag mat |
| Complete renovation with aeration and overseeding | Rake, then drag mat, broom for touching up |
| Individual spots where sand stays on top | Broom |
In a renovation, the three work as a team: first the rake pulls the sand across the area and into the hollows, then the drag mat works sand and seed evenly into the turf and channels, and finally the broom touches up the spots where sand is still on top.
When to top-dress?
Top-dressing is most effective straight after aeration, so usually in May or September, when the lawn is in full growth and the open channels are waiting to be filled. A thin layer of sand as a top-dressing to even out small bumps, on the other hand, can be applied at any time during the growing season, as long as the grass stays visible through the layer. What the complete autumn treatment looks like, from mowing short to overseeding, is explained in our article on lawn renovation in September.