How to Diagnose and Fix Lawn Problems
LESLIE: Well, weeds aren’t the only thing standing between you and the lush lawn of your dreams.
TOM: Well, that’s right. Once your turf is established, you’ve got to watch out for pests, fungal disease and even Fido. If you’ve got a mysterious brown spot or a dry patch plaguing your grass, here to tell us how to get to the bottom of it is Roger Cook, the landscaping contractor for This Old House.
ROGER: Thanks for having me.
TOM: So, let’s start by talking about one of the most common causes of lawn problems: the four-legged kind. How do we address the dog damage?
ROGER: Well, unless you’re going to chase your dog around the yard with a hose, there’s really not much you can do except try to train them to go in one area. It’s hard. The dog’s going to go where he’s going to go.
TOM: Right. But that’s kind of a special type of damage, right? The acidity from dogs and that sort of thing?
ROGER: Right. And it’s going to leave a dead circle in the ground. Sometimes, it’s real lush on the edges where it wasn’t as strong but it’ll actually fertilize the lawn. But what you have to do is stay on top of it. I usually put a little compost down, rake it in and reseed the area. Because after one rainstorm, the salts have leached out and you can reseed again.
There’s other problems that are going to pop up that’ll cause bad spots in your lawn and one of the biggest ones are the white grubs.
TOM: Grubs, OK.
LESLIE: Yeah. How do you know you’ve got them?
ROGER: You’ll know. There’ll be a patch that a grass – it’ll just die. Sometimes, you’ll get birds down picking at it, like crows, or you’ll get a raccoon that’ll come in there, a skunk and peel it back and eat the grubs.
TOM: And don’t you have more mold problems when you have grubs?
ROGER: You do. They eat them, too. But the biggest giveaway is if you take that grass and pull on it, it’s going to peel up like a rug because the …
ROGER: Yep. The grubs eat the roots off the bottom of the grass.
TOM: So what’s the solution?
ROGER: The solution is to treat the grubs when they’re most vulnerable. Usually, that’s late summer or into the fall when they’re small. If you try to treat them early in the season, they’re pretty big and pretty strong and they won’t be controlled easily.
TOM: OK. Now, what about chinch bugs? We see a lot of those in some parts of the country.
ROGER: It all depends, you know? The great thing about this country is we all have our own pests.
TOM: We’ve all got our own bugs.
ROGER: So that’s a pest of St. Augustine lawns, where it actually pierces the blade and sucks on it and makes it turn brown. There’s a lot of treatments. I like to do extra soil prep, extra watering before you turn and look at an insecticide. But in some cases, you do have to use an insecticide.
LESLIE: How would you tell if your lawn, say, had a fungus? I imagine you’re dealing with a very moist situation, on the most part, for your lawn that generally would lead to a fungus.
ROGER: Right. In some of them, it’s very easy to look at the stem and it turns brown. In some cases, there’s a fungus called “red thread disease” where the blade actually turns red and you can notice it.
And again, it’s from too much water and not drying out or fertilizing less. And those are all physical things you can do before you take and turn to spraying for the fungicide.
TOM: I think it’s interesting that every single one of these conditions is telling us something about our lawn. Something is happening that’s in excess, like excess water, we’re not getting enough water, we’re getting too much shade, we’re not getting enough shade. I mean there’s always some result of these – well, I guess the disease is the result but it’s actually leading back to a solution that has to do with lawn health.
ROGER: Right. And that’s why I’m always talking about when you put a lawn in, do the proper preparation ahead of time. Because it’ll pay off in the lawn run.
LESLIE: Now, it’s interesting. I’ve seen – because I have a dog, so I end up walking around the block quite often. I’ve seen almost a striped look on a lawn that’s usually sort of at the beginning of the season.
LESLIE: What the heck is that about?
ROGER: We call it “amateur damage.” That’s when someone goes out, particularly with a drop spreader, and fertilizes the lawn.
ROGER: And they don’t quite overlap enough, so you get those nice 4- to 6-inch strips of yellow, bright green, yellow, bright green all the way through the lawn. If you’re going to use a drop spreader, what I tell people to do is set it at half of what the normal rate is, go one direction and then turn and go exactly 90 degrees to it. You use the same amount but you’re going to eliminate 99 percent of those stripes.
TOM: We’re talking to Roger Cook, the landscaping contractor on TV’s This Old House.
So, Roger, what if we don’t have enough grass? What if instead of grass we’re getting, say, moss?
ROGER: Moss is telling you that it’s probably too shady there for grass to grow. And what we do is – then we switch to groundcovers.
You can’t fight Mother Nature. Shade is going to get worse every year as trees and shrubs get bigger and bigger, so you’re better off transitioning into a natural groundcover that will tolerate those conditions.
TOM: And what would be a good groundcover that’s kind of similar to grass, in terms of its appearance?
ROGER: Some of the sedges will work really well for you. I like things like Vinca.
LESLIE: Hmm. Vinca minor is really pretty.
ROGER: Yeah. And some of the ferns will fill in and just give you garden – work with Mother Nature. You keep seeding and putting fertilizer down and the grass doesn’t grow, she’s trying to tell you something.
LESLIE: Yeah. “I don’t want the grass here.”
ROGER: It’s not going to work. But you put down ferns and Vinca and stuff like that, she’ll love it. And they’ll grow in and fill in and you won’t have to cut them, either.
LESLIE: Roger, what if the lawn is just really in such bad shape that you want to call it quits and start over? Can you do that?
ROGER: You can, absolutely. And we use the 45-percent rule: once it gets bad to 45 percent, you’re not going to spend any more money overseeding or anything like that.
So, usually, what we do is we come in and instead of spraying with an herbicide, we like to use a sod cutter. And we take and cut off the top 2 inches so that removes all the grass, all the roots and all the weeds at one time. Then we rototill, we add compost, we rototill again and we determine whether the sand needs – whether the soil needs some sand mixed in or some more compost. And then once we get a good 4- to 6-inch and even 8-inch layer of good soil, then you can either sod or seed. So those are like the icing on the cake. If you don’t spend the money on the cake, it doesn’t matter how good the icing is on top.
TOM: Good advice. Roger Cook from TV’s This Old House, thanks so much for stopping by The Money Pit.
ROGER: My pleasure.
LESLIE: Alright. Catch the current season of This Old House and Ask This Old House on PBS. For local listings and step-by-step videos of many common home improvement projects, visit ThisOldHouse.com.
TOM: And This Old House and Ask This Old House are brought to you on PBS by The Home Depot. More saving, more doing.