Many golfers may be dismayed when they show up at a golf course expecting to find it in pristine condition, only to discover that the greens have been sanded. But green keepers don’t sand putting surfaces simply to annoy you. They do it for the long-term health of the greens.
Old Tom Morris was the greenkeeper at St. Andrews after a successful career as a golferlte is credited with accidentally discovering the virtues of routine sand topdressing to improve the density and uniformity of putting turf when he accidentally spilled a wheelbarrow of sand on a green, and the turf thrived.
But what are the benefits of sanding? How, exactly does it work? Jimmy Kidd, former superintendent of Gleneagles, in Scotland and founder of the Scottish Greenkeepers’ Association, offers his explanation. Kidd says sanding helps break up thatch, a layer of organic material that builds up over time in the upper root zone.
Too much is not good; if levels of thatch exceed roughly a half-inch, Kidd says, “the greens will suffer during extremes of drought and wet periods.” The ill effects can vary. The green might get spongy, or develop brown spots, or become vulnerable to scalping during mowing. Sanding helps protect against all that.
That’s not all, Kidd says sanding also improves drainage and helps level out the green, creating smooth, consistent putting surfaces, and firm, fast conditions year round. For all of those reasons, Kidd says, superintendents “will lightly apply dustings of sand throughout the season.”
Sanding, and how much sand is used is critically important. Sand too heavily at the wrong time of year, and you risk a range of problems. It’s best to do the work in good weather, Kidd says. In inclement conditions, you might wind up smothering the grass or creating fungus diseases that diminish the quality of the turf.
“You’ve also got to use the right kind of sand. Construction sands, for instance, are a no-no”, Kidd says. They’re made up of angular particles that are meant “to provide strength and structure.” That’s good for buildings, but bad for grass, as the sand binds together, reducing the air and water flow needed for healthy root growth.
Golf-course sands are different. They are made of round particles “resembling a bucket of balls with large pore spaces between each ball,” Kidd says. They promote good drainage, and healthy air and water circulation. Using the wrong sand, Kidd says, can adversely affect the movement of water and nutrients upwards and downwards through the root zone.
As every serious golfer knows, greens are often sanded and punched, or aerated, at the same time. That’s not always necessary, Kidd says. If the goal is merely to level the green, simple topdressing will suffice. Aeration comes in when soils are heavily compacted or the turf is thick with thatch. The greens get punched and sanded, and the sand is worked into each aeration hole to improve air and water flow, giving the roots a better chance to drink and breathe.
Caring for home lawn requires less precision than tending to a green, but many of the same principles apply. Depending on how you use your own yard, you might never want or need to sand it. But if you do, be sure to use the right sand, in the right amounts, at the right time.
If the soil is heavy, you might need to aerate to keep your turf healthy. You might not wind up with a patch of grass as pure as a putting green, but you’ll have a pretty sweet place to chip and pitch.