Lawn and bentgrass - Ask Extension
My lawn needs leveling and also contains bent grass that I would like to kill and just start over! My question is should I wait until fall or do it no...
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Lawn and bentgrass #926102
Asked March 16, 2026, 12:25 PM EDT
My lawn needs leveling and also contains bent grass that I would like to kill and just start over! My question is should I wait until fall or do it now? I do have a sprinkler system but I am not sure what to do! Is time running out now to have this done before summer? I am getting quotes on this project right now any help would be appreciated!
Medina County Ohio
Expert Response
Hi,
The concise answer to your question, is that it is probably too late to start now for spring planting. The best time to seed for Medina County is considered August 15 - September 15. Next best is early spring, preferably in March. To kill your present lawn will take some time, both to kill the lawn and for whichever herbicide you use to dissipate and be safe for seeding. Please read the label instructions for the herbicide you select and follow them strictly, waiting until your lawn is ready for seeding. This will also give you time to soil test and to receive soil test results to learn whether soil augmentation is needed to improve your soil for best lawn development. For soil testing go to https://medina.osu.edu/program-areas/agriculture-and-natural-resources/soil-and-turf-sampling. To be ready for the optimal seeding time, you will want to start killing the old lawn in summer.
For a more comprehensive guide to establishing a new lawn, please review the linked OSU Fact Sheet, https://ohioline.osu.edu/factsheet/hyg-4031. Despite its title, it is not just for organic lawns. It touches on all aspects you will need to consider.
Thank you for your question.
The concise answer to your question, is that it is probably too late to start now for spring planting. The best time to seed for Medina County is considered August 15 - September 15. Next best is early spring, preferably in March. To kill your present lawn will take some time, both to kill the lawn and for whichever herbicide you use to dissipate and be safe for seeding. Please read the label instructions for the herbicide you select and follow them strictly, waiting until your lawn is ready for seeding. This will also give you time to soil test and to receive soil test results to learn whether soil augmentation is needed to improve your soil for best lawn development. For soil testing go to https://medina.osu.edu/program-areas/agriculture-and-natural-resources/soil-and-turf-sampling. To be ready for the optimal seeding time, you will want to start killing the old lawn in summer.
For a more comprehensive guide to establishing a new lawn, please review the linked OSU Fact Sheet, https://ohioline.osu.edu/factsheet/hyg-4031. Despite its title, it is not just for organic lawns. It touches on all aspects you will need to consider.
Thank you for your question.
Dear Greg,
Thank you for your quick reply. My landscaper is advising Round up to kill the bentgrass which is covering most of my lawn front and back.
I am concerned about that and was wondering what you think. I saw that there is a herbicide called Trimec Bentgrass formula, would that be better? We have used Tenacity in the past but that did not work too well. Also, can these be used in the heat of the summer?
Thank You,
Peggy
On Monday, March 16, 2026 at 02:14:15 PM EDT, Ask Extension wrote:
Hi Peggy,
Glyphosate, an active ingredient of Roundup, is an effective broad-spectrum herbicide. It attaches quickly to the soil, limiting migration, and quickly breaks down in the soil. Trimec and Tenacity are selective and are not likely to eradicate all your present grass and weeds. Glyphosate and glufosinate are broad-spectrum leave no residue in the soil. Roundup, as noted in the FactSheet, is recommended for this use.
Whenever using any pesticide, including herbicide and insecticides, always read the label, both for being effective against your target and for application. An EPA approved label for a Roundup weed and grass product provides:
[For Lawn [Replacement/ Renovation]]
[Use [this product/ Insert Brand Name] to kill [an existing] lawn and [its] weeds before planting a new lawn [or
prior to laying a patio, sidewalk or driveway].] Alternative Text: [For lawn replacement use [this product/ Insert
Brand Name] to kill lawn and weeds before planting new lawn.]
x [Skip one mowing before spraying.] [If soil is dry, water the day before application and 2 to 3 days after
application.]
x [Use 2.5 fl oz (5 Tbs) per gallon of water for each 300 sq ft. Apply evenly over treatment area.]
x [If green patches remain after 7 days, reapply.]
x [Wait [at least] 3 days after last application to prepare the soil for planting by raking or rototilling the lawn. Rake
up and remove loosened thatch or debris.]
x [Apply seed according to directions on seed package or install sod. Grass seed must have a good contact with
soil to germinate and grow. Keep area moist for 2 weeks to establish new lawn, then water as needed.]
Be sure to read the label for your specific Roundup product--there are several.
For best results do not apply it when the weather is hot and dry. It may not be as effective on dormant grass and weeds.
If you act quickly, you may have time yet this spring.
Glyphosate, an active ingredient of Roundup, is an effective broad-spectrum herbicide. It attaches quickly to the soil, limiting migration, and quickly breaks down in the soil. Trimec and Tenacity are selective and are not likely to eradicate all your present grass and weeds. Glyphosate and glufosinate are broad-spectrum leave no residue in the soil. Roundup, as noted in the FactSheet, is recommended for this use.
Whenever using any pesticide, including herbicide and insecticides, always read the label, both for being effective against your target and for application. An EPA approved label for a Roundup weed and grass product provides:
[For Lawn [Replacement/ Renovation]]
[Use [this product/ Insert Brand Name] to kill [an existing] lawn and [its] weeds before planting a new lawn [or
prior to laying a patio, sidewalk or driveway].] Alternative Text: [For lawn replacement use [this product/ Insert
Brand Name] to kill lawn and weeds before planting new lawn.]
x [Skip one mowing before spraying.] [If soil is dry, water the day before application and 2 to 3 days after
application.]
x [Use 2.5 fl oz (5 Tbs) per gallon of water for each 300 sq ft. Apply evenly over treatment area.]
x [If green patches remain after 7 days, reapply.]
x [Wait [at least] 3 days after last application to prepare the soil for planting by raking or rototilling the lawn. Rake
up and remove loosened thatch or debris.]
x [Apply seed according to directions on seed package or install sod. Grass seed must have a good contact with
soil to germinate and grow. Keep area moist for 2 weeks to establish new lawn, then water as needed.]
Be sure to read the label for your specific Roundup product--there are several.
For best results do not apply it when the weather is hot and dry. It may not be as effective on dormant grass and weeds.
If you act quickly, you may have time yet this spring.
Thank you Greg, I have learned so much today and really appreciate your knowledge.
On Monday, March 16, 2026 at 07:13:07 PM EDT, Ask Extension wrote:
