A versatile grass species, creeping bentgrass walks a fine line between friend and foe in various landscapes. Considered a weed east of the Cascades and in many home lawns in the South, especially when mingling with other grass types, it transforms into a prized turfgrass on golf courses and lawns in regions like the Pacific Northwest.
Let’s delve into why it’s deemed undesirable in some areas and a sought-after choice in others. You’ll also learn how to handle and even leverage this perennial grass in your outdoor spaces.
What is creeping bentgrass?
Also known as carpet bentgrass, this cool-season perennial grass has successfully naturalized throughout most of the region west of the Cascade Mountains. It’s most suited for golf course putting greens, tees, and fairways rather than home lawns since it:
- Is very high-maintenance
- Needs to be monitored closely for pests and diseases
- Has higher water needs than most grasses
- Needs regular irrigation to keep its shallow root system adequately hydrated
- Has very low mowing requirements — should be mowed at 0.5 inches or less
This turfgrass has even more laborious requirements in the South. It needs frequent aeration, fertilization, and topdressing. Plus, maintenance is higher in the summer months.
However, its excellent cold-tolerance, quick spreading growth habit, and dense, carpet-like cover make it ideal for growers in the North. In fact, this grass is best adapted for the Northwestern and New England regions.
Characteristics of creeping bentgrass
You can easily identify creeping bentgrass (Agrostis palustris / Agrostis stolonifera) by its fine-textured, narrow blades arranged in a distinctive boat-shaped tip. The vernation of the grass (leaves rolled in the bud) sets it apart from other grass species. Additionally, its lush, carpet-like appearance is more noticeable due to its bright bluish-green color.
It grows low to the ground but stands out when it grows longer. It becomes puffy and forms tightly packed, irregular circular patches that disrupt the uniform appearance of the lawn.
Classification: Cool-season grass
Spreads by: Stolons
Soil type: Well-drained, moist, and fertile soil; grows in sand and organically amended sand
Soil pH: 5.5–6.5, but it can adapt to higher pH levels
Mowing height: 0.5 inches or less
Shade tolerance: Moderate to high
Drought resistance: Low
Foot traffic tolerance: Moderate to high
Maintenance needs: High
Potential for disease: High
Insect pest tolerance: Low
Note: Creeping bentgrass can end up on your lawn from seeds carried by the wind, or a runner of the plant dropped by birds. This grass can also be reproduced by stolons. Patches of the grass have several stolons or stems that enable bentgrass to spread quickly. But even a single leaf blade can take root and proliferate.
Creeping bentgrass cultivars
Here are some of the most used varieties of creeping bentgrass:
- Century: This cultivar boasts a fine texture and excellent heat tolerance, making it ideal for golf course greens.
- Cobra: With its aggressive growth habit and disease resistance, this variety establishes lush, resilient turf in various settings.
- Cohansey: Known for its adaptability, this variant thrives in both cool and warm climates.
- Emerald: Its rich green color and dense growth make this cultivar a popular selection for putting greens, providing a smooth, consistent playing surface.
- National: Prized for its superior cold tolerance and resistance to diseases, this variant can create a robust and enduring lawn or sports turf.
- Nimisilla: It exhibits exceptional drought resistance, maintaining its vibrant green appearance even in challenging weather conditions.
- Penneagle: This cultivar stands out for its fine leaf texture and excellent disease resistance, making it a preferred choice for golf courses and lawns.
- Penn Links: The fine texture and wear tolerance of this cultivar make it suitable for high-traffic areas while maintaining an attractive appearance.
- Providence: Known for its rapid establishment, providence creates a dense, resilient turf suitable for various landscaping applications.
- Putter: Ideal for golf putting greens, this cultivar delivers a smooth, consistent surface that enhances the playing experience.
- Regent: Celebrated for its dark green color and adaptability, regent excels in both fairways and tees on golf courses.
- Southshore: This cultivar is favored for its heat tolerance and quick recovery from stress, making it ideal for lawns and sports fields.
- SR1020: Recognized for its exceptional disease resistance, SR1020 creates a healthy and visually appealing turf.
- Toronto: Prized for its fine leaf texture and adaptability, this cultivar provides an attractive and resilient turf for diverse landscaping needs.
- Viper: Its aggressive growth and resistance to diseases make it a durable and visually pleasing option.
What makes creeping bentgrass an undesirable weed?
Many homeowners consider it a weed in the South and east of the Cascades, particularly when coexisting with other grass species. Let’s explore what makes this cool-season perennial grass so undesirable.
- Requires frequent mowing: Letting it grow more than 1/2 inch can cause irregular circular patches, while cutting it below 1/4 inch increases susceptibility to annual bluegrass.
- Extensive watering requirements: For newly established lawns, initial watering five to seven times a day is necessary unless mulch is used, in which case irrigation frequency can be reduced to two to three times daily.
- High fertilizer needs: Routine nitrogen fertilizer applications of 4 to 6 pounds per 1,000 square feet are needed annually during its growing season. Alternatively, you can apply one-half pound of fertilizer monthly per 1,000 square feet from October to May and reduce it to one-quarter pound per 1,000 square feet from June through September.
- Declines in the summer and requires even more maintenance: When bentgrass goes dormant, weeds can sprout.
- Does not mix well with other grasses: Its aggressive growth pattern and lateral stolon spreading make it incompatible with turfgrasses exhibiting an upright growth habit. Additionally, it doesn’t blend well with Kentucky bluegrass.
- Can invade nearby turf: Low mowing heights, as well as light and frequent mowing, encourage the turfgrass to crowd out other grasses.
- Develops significant thatch build-up: Since it tends to accumulate thatch, it requires regular dethatching, core aeration, and vertical mowing. To prevent additional summer stress, add topdressing and aerate in both fall and spring.
- Susceptible to insect pests and diseases: Creeping bentgrass is vulnerable to insect pests and diseases, especially when cut very low. It needs close monitoring and prompt pesticide treatment when issues arise.
Creeping bentgrass vulnerabilities
Creeping bentgrass is most vulnerable to the following insect pests and fungal diseases:
Pests | Lawn diseases |
Ants | Brown patch |
Black cutworm | Dollar spot |
Sod webworms | Fusarium patch |
White grubs | Gray snow mold |
Pythium blight | |
Take-all root rot | |
Yellow patch |
Note: Since warm, moist environments encourage disease development, preventive fungicides are typically needed to manage its susceptibility to many infections. Additionally, animals like troublesome voles, Canada geese, and eastern moles pose a threat to the grass.
What makes creeping bentgrass a desirable turfgrass?
For homeowners who want a refined and resilient grass cover, the following qualities of creeping bentgrass make it an excellent candidate:
- Thick, dense covering: Creeping bentgrass produces a smooth, uniform covering when maintained at very low mowing heights. The carpet look creates great curb appeal.
- Soft to walk on: The grass has a fine texture. Its leaf blades have no auricles and consist of long ligules. Cultivars range from slightly coarse to very soft.
- Good foot traffic and wear tolerance: Foot traffic tolerance and recovery are better when bentgrass is kept at longer lengths than when it’s cut as short as golf course putting greens.
- Adapts well to cold climates: As a cool-season grass, bentgrass prefers air temperatures between 60 and 75 degrees Fahrenheit. It grows best in the spring and fall. Bentgrass has excellent cold tolerance and is best adapted for the cooler climate in the Northern part of the US.
- Moderate to good shade tolerance: Creeping bentgrass grows best in full sunlight, but it adapts to light shade. If you keep the grass cut as low as heights on golf courses, the grass will need full sun for optimal growth.
How to get rid of creeping bentgrass
The best solution is to call a lawn care expert to get rid of the bentgrass invasion. But you also have a few options for eliminating this perennial grassy weed. Here are some things you can do yourself:
Mechanical methods
If there are only a few patches, the following mechanical methods can be used:
Option 1: Use a sod cutter or shovel to eliminate bentgrass patches. Get rid of stray stolons to make sure the entire plant is removed. Reseed or sod with the desired turfgrass.
Option 2: Remove patches of creeping bentgrass by solarizing them. Cover patches with clear plastic for about six days. The heat and lack of air will kill the bentgrass. Reseed immediately.
Chemical treatments
Option 1: Spot treat small lawn sections with a non-selective herbicide like glyphosate. It typically takes two or more treatments to destroy stolons underground. Reseed or sod once all the bentgrass is annihilated. Non-selective herbicides will kill other turfgrass species, so be sure you only apply the products to bentgrass.
Option 2: Use a selective herbicide like Tenacity. Treat the grass with the product three times, spaced about two weeks apart. Tenacity turns bentgrass bright white before it browns and dies. Once the bentgrass is dead, aerate your lawn first before seeding with the desired turfgrass.
How to prevent creeping bentgrass
These things can help discourage creeping bentgrass proliferation:
- Water deeply but less often: Bentgrass thrives in cool, moist conditions. Its roots are more shallow than other grass species, so infrequent watering may help the desired grass grow while simultaneously discouraging bentgrass growth.
- Do not mow the grass too short: Low mowing heights promote creeping bentgrass. Mow the grass when it is at least 2.5 to 3 inches tall.
How to establish creeping bentgrass
Homeowners desiring the attractive carpet bentgrass look, as well as its excellent cold-tolerance and ability to withstand foot traffic, can start a lawn with seeds, sod, or plugs.
Seeding is the best way to establish a lawn since sod and plugs are not as easily accessible. In the South, only seeded cultivars are used. Spread 20 seeds per square inch of soil and keep them moist until they germinate.
Estimated cost: Seed costs depend on the cultivar and purchase location. A 1-pound bag of seeds costs around $94. Expect to need 1 pound per 1,000 square feet.
When to plant creeping bentgrass
Spring is the best time to plant creeping bentgrass seeds. The grass prefers cool nights and grows best when the temperature is 55 degrees Fahrenheit.
Spread seeds on a layer of sand to help it take root. Although spring planting is recommended, you can also plant in the fall. It takes less water to maintain moist soil when you plant in the fall.
Pro tip: For successful establishment in the South, seeding creeping bentgrass should be done in early fall, allowing the grass adequate time to mature before summer stress. Common practice involves laying well-drained soil combinations amended with organics over a drainage system, providing the optimal conditions for the grass to thrive.
How to maintain an established creeping bentgrass lawn
Creeping bentgrass needs close monitoring to manage mowing heights, pests, and diseases. In the South, homeowners must monitor mowing, watering, fertilization, and diseases and pests closely, especially during the summer.
Fertilization, dethatching, aeration, topdressing, and disease and pest management practices were discussed earlier. Here are some additional tips for maintaining a creeping bentgrass lawn:
Water adequately
As stated previously, irrigation is determined by evapotranspiration. The soil’s water retention capacity is also a determining factor. The grass grows best when optimal irrigation systems are used in well-drained soil. The water needed may range from minimal to none.
For example, misting may be needed to cool the grass to mitigate mid-day stress, especially during periods of heat stress. During these periods, an excessive or deficient amount of water can harm the grass, so watch it closely.
How to determine ET and how much water the grass needs in inches:
Add up the ET for your area over three to five days. Subtract the sum of recent rainfall from the ET. Evapotranspiration and rainfall data can typically be found via online sources. You can usually get ET rates for the previous day by calling your local weather station daily.
Mow properly
Mow a newly established creeping bentgrass lawn at a height of 3/4 inches. Since this grass grows the most in the spring, mow the lawn daily during this time. Keep the grass cut no lower than 1/4 inch. Scalping injury can occur if the grass is not mowed frequently.
Provide breathing space and manage weeds
Breathing space: The grass needs well-established soil and sufficient room for air circulation. For this reason, most homeowners typically use sand.
Weed management: It is best to avoid chemicals for weed management, as they may also kill bentgrass. Instead, you should resort to manual methods. If weed management chemicals are necessary, use products formulated for sensitive turfgrass like bentgrass.
FAQ about creeping bentgrass
How long does it take creeping bentgrass seeds to germinate?
It takes about seven to 15 days for seeds to germinate, depending on soil temperature.
How does evapotranspiration help maintain creeping bentgrass lawns?
Evapotranspiration (ET) plays a vital role in maintaining creeping bentgrass lawns by influencing their water requirements. Since this grass species has high water needs, you must monitor evapotranspiration rates and adjust the irrigation schedules appropriately.
Understanding evapotranspiration helps ensure that creeping bentgrass lawns receive the right amount of water to support their health and aesthetic appeal.
Which creeping grass cultivars are commonly used in the North and the South?
These cultivars are used predominantly in the North, with limited use in the South:
- Cohansey
- Congressional
- Nimisilla
- Toronto
The seeded varieties are typically used in the South. These include:
- Cato
- Penncross
- Seaside
- SR1020
Overcome the challenges for a perfect lawn
Whether you are trying to get rid of creeping bentgrass or desiring to establish it, the process can be complicated. Eliminating the grass as a weed requires the use of harmful chemicals. Establishing it as turfgrass and maintaining it requires using the right soil and understanding how to calculate ET.
Let the experts handle your creeping bentgrass and other lawn care needs. It doesn’t matter whether bentgrass is a weed or turfgrass in your eyes — LawnLove can connect you to lawn care pros to eradicate the grass or help it thrive.
Note: Lawn Love may get a referral fee for matching you with contractors in your area.
Main Photo Credit: Daderot | Wikimedia Commons | Public domain