Grass Looks Dead After Cutting: What Should I Do?

Mowing the lawn is a North American ritual during the warm weather months. It’s something a lot of guys look forward to because it gets them out of the house, and it’s hard to beat the smell of a freshly mowed lawn. But sometimes your delightful afternoon in the yard can turn dark because, much to your horror, the grass looks dead after cutting it.

“What’s going on here?” You wonder. Have you somehow killed your lawn? The answer is: “Possibly. But not necessarily.” The fact that your lawn looks unhealthy or downright dead after you mow indicates something is not right. That much is certain. But there could be any number of factors at work causing the unhealthy appearance.

Below, I’m going to take a close look at possible reasons why your grass looks dead after mowing it.

First Things First: Is Your Grass Actually Dead?

The most important thing to determine right off the bat is whether the grass is actually dead. This is not always easy to do. So start with the big picture.

Has the entire lawn has gone brown on you, or is the problem manifest in particular areas of the lawn? If the entire lawn has gone brown it may indicate you’re mowing with a dull blade. Doing so can tear the grass rather than cutting it. This can produce loose, ragged ends on the blades of grass that turn brown. A lawn full of these brown tips can sometimes appear dead. An entirely brown lawn may also indicate the grass has gone dormant. (Something I’ll discuss at length in a few moments.)

On the other hand, patches on the lawn tend to indicate the grass in those areas has died. One simple way to confirm that the grass is actually dead is to pull some of it up. If it’s truly dead it will come up with little effort. If you have confirmed that the grass in those patches is dead, you’ll need to figure out why.

The first thing to consider is whether those areas have been getting the same amount of water as the healthy-looking areas of the lawn. It may be that sprinklers are overlapping in those areas, drowning the grass. Or perhaps water has not been reaching those areas at all.

Non-Water Related Causes for Lawn Death

If parts of your lawn are truly dead the culprit is not always water-related. Those areas may have fallen victim to disease or fungi. Leaf Spot, Red Thread and Summer Patch are diseases that often befall North American lawns. They leave behind various telltale signs such as yellow circles with dark centers (leaf spot), red threads that bind blades together before killing them (red thread), and crescent-shaped brown patches (summer patch). Grubs and pet waste may also be responsible for areas of your lawn dying off.

In addition, lawns can sometimes be suffocated by a buildup of thatch. This can happen when you wait too long to mow the lawn and you do not use a bag to collect the clippings. In such cases, the long cut ends can settle into the lawn, turn brown (this brown thatch is what you’ll likely notice first), and block the sun from reaching the lower portion of the leaf blade, causing it to die.

But again, just because your lawn looks dead doesn’t mean it actually is. This is particularly true if the whole lawn has gone brown at the same time.

So, if it’s Not Dead, Why is it the Grass Looks Dead After Cutting it?

If the grass is not actually dead but has taken on a deathly appearance, then it is probably just dormant. Dormant grass is grass that is conserving energy in an effort to stay alive. So why is your lawn engaged in this kind of wrestling match with mortality? It may be because you have cool weather grass but you live in a place that gets baking hot during the summer. Or vice versa. Maybe you have warm weather grass but you live in a place where it’s cool much of the time.

If you have not been getting as much rain as you normally do where you live your lawn may also go dormant in response to the lack of water. This is called “drought-induced dormancy” and in most cases, a lawn can stay in this state where it looks dead for about 3 or 4 weeks before actually dying off. If your lawn has gone dormant and it looks like you’re in for a prolonged dry spell, you may have to give the lawn a good, deep soak for a couple of days in a row to resuscitate it. But that doesn’t mean the color will come right back. More on that below.

Keep in mind too that if you suspect the lawn is dormant you should not mow it, and you should keep people off it, since walking or playing on a dormant lawn can damage the root system.

Can You Bring Dead-Looking Grass Back to Life?

If the grass has truly died for one of the reasons I discussed above, then there is no way to bring it back. You will have to start over by reseeding the lawn or installing new sod. Or, if your heart is broken by losing the lawn and you can’t fathom the heartache of losing another lawn, you can always replace the lawn with something else, like a garden or flagstone or some other type of groundcover. However, if the grass is dormant then your course of action will depend on the reason why it has gone dormant.

If the grass has gone dormant because it’s not a good match for the climate, then watering won’t bring it out of its funk. Rough bluegrass and bentgrass are two types of grass that are going to fold up their tent if the mercury tops 90 degrees for more than a few days in a row. Once dormant they’re going to stay that way until next spring, and nothing you can do is going to change their mind. If you have grass that is temperature-sensitive you’ll either have to accept that it may go dormant periodically, or swap it out for a more environmentally appropriate type of grass.

If the grass looks dead after you mow it but is really in a state of drought-induced dormancy then, as I mentioned above, you should give it a good soak for a couple of days in a row. That will usually snap it out of its coma and restore it to its normal healthy color, though it might take a while before you notice the color return. There may be some areas of the lawn that don’t return to normal. In which case, you will need to reseed or resod. Just make sure the grass you reseed or resod with matches what you have or your lawn will take on a quilted effect.