How much sun and shade your grass *really* needs, according to a golf-course superintendent

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What's the secret to a healthy lawn? We asked a golf course superintendent.

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Ed. note: Welcome to Super Secrets, a new series in which we’re picking the brains of the game’s leading superintendents. By illuminating how course maintenance crews ply their trades, we’re hopeful we can not only give you a deeper appreciation for the important, innovative work they do but also provide you with maintenance tips that you can apply to your own little patch of paradise. Happy gardening!

When we say that someone has it “made in the shade,” we mean they’ve got it good and easy. But for fairways, greens and tees boxes, it’s a different story: shade isn’t always an easy place to be.

Few people know this better than golf course superintendents, who are all too familiar with the potential problems that lurk in the shadows.

Matthew Guilfoil is the superintendent at Desert Canyon Golf Club, in Arizona, and co-host of the turf care-focused podcast From the Jingweeds, so he’s good for shedding light on these shady matters, and what homeowners can learn from them.

Here are four things to know when tending to your own yard:

1.  Let there be light

Different strains of grass have different strengths and weaknesses. Some need more water, others more sunlight. As a general rule, cool-climate grasses like, say, bentgrass, are more shade-tolerant than warm-climate strains such as Bermuda, which, Guilfoil says, requires a minimum of six hours of direct sunlight a day.

In Guilfoil’s experience, morning sun is best, though he concedes that “in all my years in the business, I’m still not sure why.” (One of his theories is that in the morning, the grass is just waking up and rearing to go, so it responds more energetically than it does at the end of a long day).

Bottom line: grasses like Bermuda need a lot of light, so if that’s what you’ve got planted in your yard and that yard is shaded by a tree, you could do the grass a favor by trimming and pruning the tree branches to let more sunlight in. Another option, Guilfoil says, is to swap out that Bermuda for a more suitable alternative, like St. Augustine, a shade-tolerant warm-weather grass.

2. Don’t dampen your prospects

It’s simple science: shaded areas of turf do not dry out as quickly as sun-splashed ones. The ground tends to get soggy. Diseases creep in. You’ve probably noticed this when you’re playing golf. Wet places are tough places for grass to grow. What’s true on the course is true in your yard. One obvious home remedy, Guilfoil says, is to give those shady spots in your yard less water. But that can be tricky if you’re relying on an automatic sprinkler or irrigation system.

If your yard is shaded by a tree, that tree might help by drinking up some of the excess moisture. But if the shade is created by a wall or your home, no such luck; neither of those will help siphon off moisture. Whatever the case, another way to deal with a stubbornly damp spot is to aerate the ground more regularly (Guilfoil recommends you do this at least once year).

Aerating will give that water somewhere to go, down, down, down into the soil, instead of simply puddling on the surface. As a side benefit, the roots of the grass will also be forced to extend deeper into the soil to get that water, and the deeper the root system, the healthier the grass.

3. Root out any problems

Trees don’t just throw shade. They pose problems with their roots. On golf courses, tree roots growing just below the turf are notorious for damaging mower blades (and for injuring golfers’ wrists). Because they outcompete grass for nutrients and water, tree roots are also a common cause of brown spots on tees and greens. In your yard, something similar applies. Grass with roots running through it isn’t nice to look at, or great to play on.

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The best way to mow your lawn, according to a golf-course superintendent
By: Josh Sens

So, what to do? When superintendents come across a troublesome underground root, they use a specialized machine to remove it. But when the root has erupted through the turf, Guilfoil says, it’s easy enough to do the job with an axe or a hatchet. “Just a couple of whacks and out it comes,” he says. “You can do the same thing in your yard.” Hacking out that meddlesome root won’t harm the tree, Guilfoil says. And it will do your yard a world of good.

4. Control the shadows of spring

In certain regions of the country, just before Bermuda grass goes dormant for the winter, superintendents overseed (most often with cool-climate ryegrass) to keep their courses looking good and playing well. Some homeowners do this in their yards, too. While there’s nothing wrong with this, problems can arise when the Bermuda begins to reawaken and finds itself in the shadow of the taller ryegrass. Yes, that’s right. Grass can throw shade, too.

“Remember, that Bermuda needs direct sunlight,” Guilfoil says. “And it’s not going to get as much with the ryegrass standing over it.”

What does that mean? It means that, as spring approaches, it’s time for that ryegrass to go. One way to rid your overseeded turf of ryegrass is to cut back on watering; ryegrass does not fare nearly as well in dry conditions as Bermuda. But a better method, Guilfoil says, is to lower your mower blade and cut everything down to the same low height, so the ryegrass is no longer shading the Bermuda.

Golf courses do this. You can do it, too, gradually, in a series of mowing sessions. Come spring, the ryegrass will be gone and the re-emergent Bermuda will stand healthily in its place.

Josh Sens Editor

A golf, food and travel writer, Josh Sens has been a GOLF Magazine contributor since 2004 and now contributes across all of GOLF’s platforms. His work has been anthologized in The Best American Sportswriting. He is also the co-author, with Sammy Hagar, of Are We Having Any Fun Yet: the Cooking and Partying Handbook.