Brown Lawn in July? Dormant Grass Explained

A brown lawn in summer is usually dormant, not dead. Common Canadian lawn grasses like Kentucky bluegrass and fine fescue shut down in hot, dry weather to protect their roots. A healthy lawn can stay brown for several weeks and green up again when rain and cooler weather come back. The City of Calgary says to worry if the grass pulls out easily or browns in distinct patches.

Why does grass turn brown in summer?

Your lawn is protecting itself. Most lawns in Canada are cool-season grasses. UNH Extension lists the usual mix: Kentucky bluegrass, fine fescue and perennial rye. It says these grasses go dormant on their own in hot, dry weather.

Dormant means the grass stops growing. Utah State University Extension says the blades turn brown and growth stops completely. The blades aren't the part that matters, though. The crown is.

The crown sits right at the soil surface. Utah State says blades grow up from it and roots grow down from it. As long as the crown stays alive, the grass can come back when the weather turns.

Iowa State University Extension calls dormancy a natural survival trick for Kentucky bluegrass. The leaves die off, but the crowns and roots stay alive. So that crunchy brown lawn in late July is often just asleep.

Grass also goes dormant in winter. The City of Calgary says it shuts down and turns brown then too, to save water and nutrients. Brown in summer and brown in winter are the same survival move.

How long can a lawn stay dormant?

Longer than most people expect. Here's what the official sources say:

• Health Canada: a healthy lawn can survive several weeks in a dormant state.
• Iowa State: Kentucky bluegrass and other cool-season grasses can stay dormant for 4 to 6 weeks without serious damage.
• UNH: a lawn in good shape should go dormant in summer without much harm.

There's a limit, though. UNH says a bad enough drought can kill grass. Utah State says dormancy is a protective process that should not be feared. It says to be patient, because the grass recovers in the fall.

The healthier the lawn was in spring, the better it handles a dry July. Thick grass with deep roots has more to fall back on.

Is my lawn dormant or dead?

The City of Calgary gives two simple checks. It says your grass may be dead if:

• you can pull the grass out easily, or
• the brown is not even across the lawn, with distinct brown patches.

Try it yourself. Grab a small handful of brown grass and give it a gentle tug. If it holds tight to the soil, the roots are still working. If it comes up in your hand with no fight, that spot may be dead.

Now step back and look at the whole yard. A dormant lawn tends to brown all over. Ohio State University's turf team says shaded parts of a dry lawn may still stay green. So a lawn that's tan in the sun and green under the maple is acting normal.

A few odd brown spots in an otherwise green lawn are different. That pattern points to something else going on in those spots.

What are the early signs before it turns brown?

UNH Extension says wilting grass shows three signs:

• The leaf blades fold in half the long way.
• The colour turns bluish grey.
• Your footprints stay in the grass for a while after you walk on it.

If you spot these, the lawn is running out of water. Dormancy is close.

What else turns a lawn brown?

Dry weather isn't the only cause. A few others are easy to rule out:

• A dull mower blade. Ohio State says dull blades fray the leaf tips and leave brown patches. Look closely at a blade of grass. A torn, ragged tip means the blade needs sharpening. Our post on sharp mower blades shows what to look for.
• Scalping. Ohio State says cutting off more than one third of the blade can badly damage or kill grass, mostly in summer stress. Bumps and high spots scalp first.
• A new lawn. Iowa State says lawns seeded or sodded this year or last may not survive dormancy. Their roots aren't deep enough yet.
• Heavy traffic. A trailer parked on the lawn all August, or a well-worn path to the shed, can leave its own brown mark.

Some brown patches come from insects or disease. Our partner crews don't spray, and Golden Oak gives no pesticide or fungicide advice.

It's fall now. Did your brown lawn come back?

This is the best time of year to find out. Iowa State says dormant lawns green back up once the weather cools and more moisture comes in the fall. Calgary says cool-season grasses turn green again when the right temperature returns.

So walk the yard after a few cool, rainy weeks in September. You'll likely see one of three things:

1. All green again. It was dormant. Nothing more to do.
2. Mostly green with thin spots. The lawn came back, but some weaker patches struggled.
3. Brown patches that won't change. Try Calgary's pull test on those spots. If the grass lifts out easily, it's likely dead.

Take a photo of any patches that stayed brown. Next spring you'll know exactly where they were. Fixing dead patches means seeding or sod, which our partner crews don't do.

One catch: grass slows down and browns again as winter gets close. Don't mistake late fall browning for summer damage. Our post on when grass stops growing explains that part of the year.

Can I water a dormant lawn back to green?

Sometimes, but not always. Utah State says that past a certain level of heat and drought, no amount of water will pull grass out of dormancy. It recovers on its own as temperatures drop.

You also need to pick a lane. Iowa State says not to let a lawn slip in and out of dormancy all summer. Only wake it up if you can keep watering after that. Ohio State says the same: once you start watering, keep a regular schedule.

If you let it stay brown, a small drink still helps. Utah State calls this "survival watering." For cool-season grass in Utah, it says as little as 2.5 cm (1 inch) of water a month can keep the crowns alive. You can give it all at once or split it into two or three waterings. It won't make the lawn green, but it helps the crowns survive.

Many Canadian cities limit lawn watering in summer, so check your city's rules first. Our post on the best time to water your lawn covers timing.

Should you mow a brown, dormant lawn?

No. Ohio State's turf team says to avoid mowing dormant and drought-stressed lawns. The cut itself is a stress, and so are the footsteps and tires. It says tire tracks from mowing can make the damage worse.

Iowa State says to keep moderate to heavy foot and vehicle traffic off dormant lawns. That traffic can damage the crowns, and hurt plants may not fully recover when rain returns.

A dormant lawn barely grows anyway. If a few tall weeds poke up, they can wait a week or two. Our post on mowing in heat and drought covers what to do while the lawn is still green but stressed. For a normal mowing rhythm, see how often to mow in Canada.

How can you help your lawn handle next summer?

Most of it comes down to how you mow, starting in spring:

• Mow tall. Health Canada says grass cut at 6 to 8 cm (2.5 to 3 inches) grows deeper roots and comes in thicker. UNH says taller grass shades the soil and keeps it cooler.
• Take off one third or less. That's how you avoid scalping in July.
• Keep the blade sharp. Clean cuts mean fewer brown tips.
• Leave it long into fall. Calgary says to leave grass longer from the end of August and let it grow into dormancy.

Our mowing height guide for Canada shows how to check your mower's real cutting height.

Want a crew that knows when not to mow?

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Book lawn mowing for the Worry-Free Lawn Season and your first cut is free. Away for a few weeks in summer? Pause by text.

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Brown Lawn and Dormant Grass Questions

Sources: City of Calgary lawn care, Health Canada, maintaining a lawn, Iowa State Extension, summer dormancy, Utah State Extension, brown grass is dormant, Utah State Extension, dead or dormant, UNH Extension, lawns in drought, Ohio State, managing lawns in drought, Ohio State Extension, lawn mowing.