The grasses can be classified as either C3 or C4 plants. Cool-season grasses are known as C3 plants and these plants are adapted to cool season establishment and growth in either wet or dry environments. C3 and C4 refer to the different pathways that plants use to capture carbon dioxide during photosynthesis.
The common cool-season grasses in the United States are: Kentucky bluegrass, perennial ryegrass, creeping bentgrass, fine fescue, and tall fescue. In this post, we will go over how to identify these grass types, the pros and cons of each cool-season grass type, and more.
Kentucky bluegrass
Kentucky bluegrass is one of the most popular grass types among homeowners that live in the cooler, northern states. This grass type originated from Europe in the 1600’s. Kentucky bluegrass is commonly used in home lawns, parks, sports fields, golf courses, as well as roadsides. If you are looking to have a beautiful lawn and don’t mind a higher maintenance grass type, Kentucky bluegrass, aka KBG, is the best grass type for you.
How Kentucky bluegrass Grows
Kentucky Bluegrass grows pretty quickly, and this grass type is primarily established from seed, but can also be established by sodding. Kentucky bluegrass forms a dense cover due to its vigorous rhizome system. Because of slow germination, Kentucky bluegrass is often planted with perennial ryegrass, as this grass type is quicker to establish.
How to Identify Kentucky bluegrass
Kentucky Bluegrass is characterized by it’s dark blueish/green color with medium-textured blades that are 2-4mm wide and have a boat-shaped tip. Kentucky Bluegrass also has a folded vernation with a triangular shaped seed head.
Pros of Kentucky bluegrass
- Good drought tolerance
- Recovers from stress quickly
- Forms a very thick, dense lawn
- Weed resistant
- Tolerant of cold winters
Cons of Kentucky bluegrass
Kentucky bluegrass has poor heat tolerance and will go dormant during extreme heat. However, once the heat subsides Kentucky bluegrass should regenerate.This grass type has poor shade tolerance, although shade can be slightly helpful to this grass type during the humid times of the summer. Kentucky bluegrass can take a long time to establish which can be frustrating for some homeowners, especially those who have a shorter season up north. This grass type can be higher maintenance as it requires a fertilization program to truly thrive. This grass type is not very wear tolerant, but with the right care it can recover from stress quickly which is why it is used in sports fields.
Creeping bentgrass
Creeping bentgrass is one of the most popular grass types among golf courses in the cooler, northern states. This grass type is extremely high maintenance and therefore is not recommended for home lawns.
How Creeping bentgrass Grows
Creeping bentgrass grows quickly, and this grass type is one of the most quickly established turfgrasses. Creeping bentgrass can be established by seed or vegetatively. Creeping bentgrass forms a very low growing, dense textured turf.
How to Identify Creeping bentgrass
Creeping bentgrass is characterized by it’s dense, low growing habits with fine blades of grass that are 1-3mm wide and possess a roughness around the edges. Creeping Bentgrass also has a rolled vernation with a more narrow, triangular shaped seed head.
Pros of Creeping bentgrass
- Great for golf courses
- Recovers from stress quickly
- Forms a very thick, dense lawn
- Tolerant of cold winters (grows well in Canada)
Cons of Creeping bentgrass
Creeping Bentgrass is an extremely high maintenance grass type. Because of this, it is not generally used on home lawns. Creeping Bentgrass should be mowed extremely low (0.125 - 0.75 inches), which causes this grass type to need to be mowed every few days. Creeping Bentgrass also has extremely high fertilizer and watering requirements. This grass type is also susceptible to fungal diseases.
Fine Fescue
Fine fescues are most commonly mixed with other cool-season grass types such as Kentucky bluegrass and perennial ryegrass. Fine fescues grow really well in states like Minnesota. These grasses offer great shade and drought tolerance but are rarely used on their own.
How Fine Fescue Grows
Some Fine fescues grow in a bunch-like manner, while other varieties can slowly spread via rhizomes. This grass type is primarily established from seed because of its fast germination rates.
How to Identify Fine Fescue
Fine fescue is characterized by thin leaves that are typically less than 0.5 mm wide and possess a bristle-like appearance. Fine fescue also has a folded vernation with a more narrow-shaped seed head and a narrow collar.
Pros of Fine Fescue
- Low maintenance
- Well adapted to dry conditions
- Good shade tolerance
Cons of Fine Fescue
Fine fescue can be sparse especially if it grows in a bunch-type habit. This grass type does not respond well to over-fertilization and can actually thin out due to too much fertilizer. Fine fescue does not tolerate damp, poorly drained soils.
Tall Fescue
Tall fescue is one of the most popular grass types for cool-season lawns along with Kentucky bluegrass. This grass type is also used on public areas and other low maintenance areas. It is a great choice for transition zone lawns.
How Tall Fescue Grows
Tall fescue has a bunch-type growth habit, and forms a low density turf that can take a while to recover from wear. Tall fescue can be established by seed or vegetatively.
How to Identify Tall Fescue
Tall fescue is characterized by its thick blades of grass that are 5-10mm wide. Tall fescue also has a rolled vernation with a narrow shaped seed head. This grass type grows in a bunching manner and tall fescue lawns can appear slightly less uniform because of this growth pattern.
Pros of Tall Fescue
- Good wear tolerance
- Good drought tolerance
- Excellent disease/insect resistance
- Good shade tolerance
- Can tolerate hot summers (good grass type for the transition zone)
Cons of Tall Fescue
Tall fescue is not the favorite choice of homeowners due to its coarse leaf texture and clumpy growth. Tall fescue prefers to be mowed high, and it must be cut no lower than 2 inches. This grass type is not as tolerant of harsh winters as the other cool-season grass types.
Perennial ryegrass
Perennial ryegrass is commonly used on home lawns in the cooler regions of the United States. This grass type is also often mixed in seed blends with Kentucky bluegrass and fine fescues. This grass type is also commonly used on golf courses and public areas, as well as for overseeding dormant warm-season lawns.
How Perennial ryegrass Grows
Perennial ryegrass grows quickly, and this grass type is one of the most quickly established turfgrasses. Perennial ryegrass is easy to establish by seed because of its quick germination rates, which are only a few days compared to Kentucky bluegrass which can take up to 3 weeks to germinate. This grass type also has a bunching growth habit, and because of its quick establishment it can easily choke out other grass types.
How to Identify Perennial ryegrass
Perennial ryegrass is characterized by it’s dense, clumping growing habits with medium textured blades of grass that are 2-5mm wide. Perennial ryegrass also has a folded vernation with a very narrow seed head.
Pros of Perennial ryegrass
- Rapid germination, quick establishment
- Great for winter overseeding
- Used for preventing erosion
- Good wear tolerance
Cons of Perennial ryegrass
Perennial ryegrass can be medium to high maintenance. Perennial ryegrass should be mowed low (1.5 - 2.5 inches), and should only be mowed with a very sharp blade due to the toughness of the turf. Perennial ryegrass is not shade tolerant or drought tolerant, and cannot tolerate extreme temperatures compared to the other grass types. Too much Perennial ryegrass can be invasive, and choke out other grass types if there is a large percentage of Perennial ryegrass in the mixture.
Which Grass Type is Best for My Location?
There are a good variety of cool-season grasses, and depending on where you live one grass type may be more suitable than the other. If you live in the transition zone where summers are hot but winters are cold, you may want to consider planting Tall Fescue due to its superior heat tolerance.
If you are located in the northeast, most any cool-season grass type will do, but the most popular grass type is Kentucky bluegrass. If you live in the northwestern states, you may want to grow Kentucky bluegrass as well, as this grass type has a decent drought tolerance compared to the others and prefers drier climates over humid. Keep in mind that there are cool-season grass type mixtures available, and sometimes your region may be better suited to 2 grass types growing in tandem rather than relying on one grass type.
