How to Care for Different Types of Grass

How to Care for Different Types of Grass

Cool Season Grasses vs Warm Season Grasses

By  | Lawn Mower Product Expert
By  | Lawn Mower Product Expert

What homeowner doesn’t want a great-looking lawn? To take proper care of your turf, it helps to understand the type of grass you’re growing and mowing.

You might have heard of cool-season grasses and warm-season grasses. But what do those categories mean? Where do types of like Kentucky bluegrass and St. Augustine grass fit into those groups?

Knowing the differences between cool- and warm-season grasses can help you give your lawn the care it needs. Get ready to learn about the various kinds of cool-season and warm-season grasses, the pros and cons of growing each, and the best practices for maintaining them!

 

Cool-Season Grasses

FescueA lush, green lawn might not be the first image you picture when someone starts talking about cool temperatures. But cool-season grasses get their name because they start growing when the soil temperature reaches about 40 to 45 degrees Fahrenheit. They reach their optimal growth at soil temperatures between 65 and 75 degrees.

This means that, in the United States, the peak growing seasons for cool-season grasses are spring and fall.

Cool-season grasses flourish in the northern parts of the country, where they’re most likely to enjoy their ideal temperatures:

  • New England
  • Great Lakes region
  • Upper Midwest
  • Upper Plains states
  • Pacific Northwest

However, grasses that are more tolerant of heat fare well in what’s known as the transition zone, an area of the country that stretches from east to west between warm and cold states, along the line where Kansas and Oklahoma sit.

 

Types of Cool-Season Grasses

From species like Kentucky bluegrass that homeowners love to the ones like creeping bentgrass that golf course groundskeepers prefer, there are cool-season grasses to suit almost every kind of use.

COOL-SEASON
GRASSES
Kentucky
Bluegrass
Fine
Fescues
Tall
Fescue
Perennial
Ryegrass
Creeping
Bentgrass
Heat
Tolerance:

 Medium

Low   High  Medium Low 
Cold
Tolerance:
 Medium
to High
 Medium
to High
 Medium Medium  Medium 
Sun/Shade
Tolerance:
Prefers Lots
of Sun 
Prefer
Shade 
 Prefers Sun,
Can Tolerate Shade
 Prefers Lots
of Sun 
 Prefers Sun,
Can Tolerate Shade 
Resistance
to Wear:
High  Medium  High  High  High 
Irrigation
Needs:
Needs Well-
Drained Soil 
Need Well-
Drained Soil 
Needs Well-
Drained Soil  
Needs Lots of Water  Needs Frequent Watering 
Additional
Notes:
Spreads 
Quickly 
Low Maintenance   Low Maintenance   Grows Quickly
from Seed
Used for Outdoor
Activity Spaces
- Not Suited
for Home Lawns 

 

How to Care for Cool-Season Grasses

Irrigation: Generally speaking, cool-season grasses need about 1” of water per week between late spring and early fall. This amount can vary due to all sorts of conditions, such as the amount of rainfall received or the type of soil on your property (clay soil holds moisture well and needs less frequent watering).

 

Fertilizing:  The best time to fertilize cool-season lawns is in fall, usually September, when they’re actively growing and can use the fertilizer to strengthen themselves before winter. Applying it at a rate of one pound of nitrogen per 1000 square feet is recommended.

Need more information about figuring out how much fertilizer to apply? Check out our Ultimate Fertilizer Guide!

 

Mowing: Cool-season grasses like Kentucky bluegrass and perennial ryegrass are best mowed at taller heights between 2½” and 3½”. True to its name, tall fescue can be left to grow even taller and mowed to a height between 3” and 4”. Creeping bentgrass should be mowed extremely short, about ½” because of its dense growth—another reason it’s preferred for professionally maintained grounds and not home lawns.

 

Warm-Season Grasses

CentipedegrassIf cool-season grasses are the ones that thrive in mild temperatures, then it’s pretty easy to guess the conditions in which warm-season grasses thrive.

Warm-season grasses begin growing at a soil temperature between 60 and 65 degrees Fahrenheit. They achieve their optimal growth when the temperature reaches a balmy 90 to 95 degrees.

This means that, in the United States, the peak growing season for warm-season grasses is summer, the warmest season of all.

Because of their temperature needs, these grasses are found most commonly in the southern parts of the country:

  • States along the Gulf of Mexico
  • States along the southern Atlantic coast
  • Inland southeastern states
  • Parts of southern California

Grasses that are hardier in the cold, such as bermudagrass and zoysiagrass, also do well in the transition zone.

 

Types of Warm-Season Grasses

Just like with cool-season grasses, you’ll find warm-season grasses suited to just about every kind of purpose, from decorative use in homeowner lawns to high-traffic use in parks.

WARM-SEASON
GRASSES
Centipedegrass Bermudagrass Zoysiagrass Bahiagrass St. Augustine
Heat
Tolerance:
 High  High High  High  High 
Cold
Tolerance:
Low to
Medium 
 Medium Medium  Low to
Medium 
 Low to
Medium 
Sun/Shade
Tolerance:
Prefers Sun,
Can Tolerate Shade 
Needs Lots
of Sun 
Prefers Sun,
Can Tolerate Shade  
 Prefers Lots
of Sun
 Prefers Lots
of Sun
Resistance
to Wear:
 Low High   High Low   Low 
Irrigation
Needs:
 Needs Little
Water
Needs Lots
of Water,
Lots of 
Drainage 
 Needs Little
Water
 Needs Little
Water
 Needs Lots
of Water,
Lots of 
Drainage
 Additional
Notes:
Low Maintenance;
Grows Slowly 
Popular Choice
for Activity 
Spaces 
 Low Maintenance Low Maintenance;
Sprouts Slowly  
Grows in 
Wide Variety
of Soil
Conditions 

 

How to Care for Warm-Season Grasses

Irrigation: One of the reasons that warm-season grasses are so tolerant of warm, dry weather is that they develop deep roots that help them survive in such conditions.

As a result, warm-season grasses generally need less water than their cool-weather counterparts. Supplying about ½” to 1” of water per week during the active growing season is suggested, though this amount will vary depending on local conditions.

 

Fertilizing: For any type of grass, the best time to fertilize it is the start of its active growing season, or immediately before it. Warm-season grasses benefit most when fertilizer is applied in late spring or early summer.

Again, warm-season grasses tend to need less care than cool-season ones. In many cases, applying one-half pound of nitrogen per 1000 square feet will do, though you should perform a soil test to most accurately determine your lawn’s needs.

 

Mowing: Warm-season grasses grow best when mowed to shorter heights; for most of them, a mowing height between 1” and 2” works well.

St. Augustine grass can be allowed to grow taller and mowed to 2½”, while bermudagrass and zoysiagrass can tolerate shorter heights between ½” and 1” (though keeping bermudagrass and zoysiagrass between 1” and 1½” during the growing season is recommended for good health).

 

Grass Seed Blends and Mixtures

Grass Seed HeadIf you want to grow cool-season grass from seed, you might find the bags on the shelf labeled as grass seed mixtures or grass seed blends.

Be careful! Grass seed blends are not the same thing as grass seed mixtures.

Grass seed blends contain different varieties of the same species of grass. It might sound strange, but you can buy a 100% Kentucky bluegrass blend.

The carefully cultivated varieties inside the blend (or cultivars) have slight genetic differences. Compare it to a dog with brown fur and another dog of the same breed with grey fur—they’re both dogs, just with different traits.

In the case of a cool-season grass seed blend, the different cultivars might be bred for traits like resistance to different diseases. This gives your grass better odds of surviving no matter what conditions may come.

Lawn in both Sunlight and ShadowGrass seed mixtures are different. They contain different species of grass. A common mixture you’ll find is a mix of Kentucky bluegrass, tall fescue, and several fine fescues.

Mixtures are excellent for yards with several different growing conditions. If half of your yard gets a full day of sunlight and the other half spends most of the day in the shade, a seed mixture might be your best option.

You’ll notice that mixtures and blends are generally created with cool-season grass seeds. Warm-season grasses grow so robustly and quickly that each cultivar is usually planted and grown by itself as what’s called a monostand.

 

Is My Lawn Dead or Dormant?

Fallen Leaves on a Mix of Dormant and Active GrassBoth cool and warm-season grasses experience periods when they’re not actively growing, also called dormancy. While they’re dormant, your lawn might look brown, thin, or patchy.

Cool-season grasses go dormant during the warmest months of summer and the coldest months of winter, while warm-season grasses go dormant during the cool stretch of time from late fall until early spring. Either type can go dormant during a heavy drought.

Although it can be hard to tell the difference between dormant grass and dead grass, one simple way to check is to tug quickly and gently on a handful of some of your brown grass. If it comes loose with very little force needed, it’s likely to be dead. Have a landscaping professional examine it for further recommendations.

If, however, it feels firm and can’t be pulled out easily, chances are that it’s dormant but perfectly healthy and will bounce back to green life once the prime growing season arrives.

And now that you know when the prime growing season is for the type of grass on your lawn and what you have to do to maintain it, you have the basic information you need to get your lawn greener and healthier than ever.

 

 NEXT: 6 Tips for Easy Landscaping