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How to Kill and Replace Your Lawn

August 3, 2015

This “kill and replace” strategy is for lawns troubled by the kind of grassy weeds you can’t kill without killing your good grass and for lawns you are fighting a constant battle with lawn diseases. We are approaching the best time of year to renovate cool-season grass lawns (like Bluegrass, Ryegrass and Fescue). Note: warm-season grass lawns (like Bermuda, Zoysia, St. Augustine and Centipede) are best started in late spring.

Starting over allows you to use today’s top-of-the-line seed blends that do a better job of tolerating drought and attacks by insects or disease. Starting over may be the best way to get rid of perennial grassy weeds such as Dallisgrass, Nimblewill, Bentgrass, Orchardgrass, Tall Fescue clumps, or Quackgrass that you can’t kill without killing your good grass too.

This 20 year old lawn contains weak grass varieties making it a good candidate for the "Kill and Replace" strategy.

This 20 year old lawn contains weak grass varieties making it a good candidate for the “Kill and Replace” strategy.  (click photo to enlarge)

Here are the steps to renovate a lawn by killing the existing grass and establishing a new lawn:

Step 1: Mid-August, spray your bad lawn area with Roundup (click here for more info). Be sure to use regular Roundup and not one of the special Roundup products that provide longer term weed prevention.

Step 2: About a week later do a repeat spray of Roundup on any areas you missed.

Step 3: A week later mow your dead grass as short as possible removing the clippings as you mow. Rent a Dethatcher (also known as a Power Rake) and run it over the dead lawn in two directions. Set the machine low enough so that the blades are touching the soil. Rake up the dead grass and add Scotts Turf Builder Lawn Soil (click here for more info) to any low spots. If you now have mostly bare soil with the top inch or so broken up you could skip the next Slit-Seeder step and broadcast your seed using a Scotts Spreader.

If you have more dead grass than bare soil, rent a Slit-Seeder to plant the grass seed through the dead lawn. with Scotts best seed blend for your situation.

Step 4: It is now early September… a great time to plant bluegrass, ryegrass and fescue. First you select the best seed blend for your situation. The best Scotts grass seed blends are in the Scotts Turf Builder Grass Seed line (click here for more info). Choose a blend rated for Sun, Sun/Shade, Dense Shade, High Traffic, Heat-Tolerance or one of the other special blends. I am a big fan of Scotts Turf Builder Grass Seed Heat-Tolerant Blue Mix.

Step 5: Spread Scotts Starter Food for New Grass (click here for more info) the same day you seed.

Step 6: Water a couple of times a day for several weeks.

Step 7: Mow your new lawn when it is tall enough to cut with the height set at around 2-1/2 inches.

Step 8: About a month after seeding, feed your new lawn with Scotts Turf Builder Lawn Food (click here for more info). Do not use any weed controls on your new lawn until your new grass has been mowed 4 times.

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  1. Dan permalink

    Hi Ashton, I live in Charlotte, NC. My front lawn is beautiful tall fescue but my back lawn has been overrun by Bermuda grass. I have tried to beat it back over the last three years. Each Spring the tall Fescue looks amazing but then by the end of the summer the Bermuda grass has overrun it again. I am leaning towards killing everything with Roundup and starting over. I typically will aerate and seed the first week of September, maybe the second at the latest. Is it too late to kill everything with RoundUp? How many successive weeks of RoundUp will it take to make sure the Bermuda grass is dead? I don’t want to go through the whole process just to have the Bermuda grass survive and slowly return. If I am going to do it, I have to make sure every last vestige of the Bermuda grass is dead or it will slowly come back and take over again for sure! Thanks for your advice

    • Hi Dan
      You are living in an area where both Bermuda Grass and Fescue can grow well. Bermuda likes sunny areas and wants to be fed 4 times a year beginning when you see 50% green up in spring coming out of dormancy with follow up feedings at 2 month intervals thru summer (for example: March, May, July, September). Because of the heat and humidity during summer and the prevalence of Brown Patch fungus disease, Fescue in your area likes some shade and likes to be fed 4 times a year during the cooler months (for example: Early March, Early September, Mid October, Late November). To do a complete kill and start over I suspect you would need to spray your Bermuda at least twice, maybe even 3 times. You have time to do this (spray now and again in 7 to 10 days), however I suspect that in your sunny areas you may still get some Bermuda returning because of how persistent it can grow back from even a small piece of root. If you decide to allow the two grasses to coexist with aerating and seeding fescue in fall, you should follow the feeding schedule for the Fescue and not the Bermuda. Hope I have helped you make a decision.

      • Dan permalink

        Thanks for your help. Yes, I’m committed to getting rid of the Bermuda because I’m afraid it will get into my gardens, front yard, etc. It’s strange because my front yard gets a lot of direct sun and my backyard tends to have more shade and stay more wet but for some reason it has taken hold there. I may hit it once this year with Round Up and then seed with Fescue in early September. Then maybe I’ll devote next summer to eradicating it entirely. It usually doesn’t come out of dormancy until the end of June so I can hit it with Round Up over and over again until I don’t see anything coming back. Then I’ll start fresh again in September. That means I’ll have dirt for a back yard from July until October when my new Fescue seed starts popping up again.

  2. Hi Dan
    If you go that route along with the feeding program that favors your Fescue and not your Bermuda you will make the Fescue stronger and the Bermuda weaker. So your three feedings this fall would be Starter Lawn Food when you seed, Turf Builder 4 to 6 weeks later and Turf Builder WinterGuard in November.

    • Dan permalink

      Great to know. I appreciate your advice.

      • Hi Dan
        Should also mention to do an early spring March feeding (possibly with a crabgrass preventer) when the fescue is growing strong and the Bermuda is still dormant. Then back off all feedings until next fall. This way you are not stimulating the Bermuda during the time when it likes to be fed.

      • Dan permalink

        OK. Yes, I always do a Spring feeding. I’ll make sure to not fertilize when the Bermuda is kicking in.

  3. Mike permalink

    what type of grass seed would you recommend for the Va. Beach, VA area (zip code 23454)

    • Hi Mike
      In Virginia Beach you can grow the Turf Type Tall Fescues, especially if you have some shade. Scotts Heat-Tolerant Blue is a good choice. You can also grow Bermuda and Zoysia. They both like full sun, however Zoysia can take some light shade. Many folks like the Fescues because they will stay green in winter while Bermuda and Zoysia go dormant (turn brown). You can seed Fescues at the beginning of Sept, however you would do better to wait till next spring to seed Bermuda or Zoysia. Hope this helps.

      • Mike Callan permalink

        Thanks, Ashton. I will see if I can acquire the Heat-Tolerant Blue that you reference. I have not used this type of fescue before, so I will be curious about the results.
        Thanks again.


      • Hi Mike
        Scotts Turf Builder Heat-Tolerant Blue Mix is a blend of three turf-type tall fescues with Thermal Kentucky Bluegrass. Here is a link to one of my blog postings that gives more info and shows a map where this blend works well:
        Good luck with your lawn.

  4. Jim permalink

    I did this to our front yard 3 years ago and the lawn looked great. Already started on the back yard this year since the deck is almost done. However the front lawn took on some stress due to the summer we had this year. How often should you reseed? I used Scotts’ Thermal Blue Mix and love the dark green. People who walk by are always talking about my yard and I mention your website for instructions and tips.


    • Hi Jim
      Good to hear of your success converting your lawn 3 years ago with Heat Tolerant Blue. You will find that this blend typically recovers well from the dog days of summer. Feeding this fall at least twice really makes a difference. You may find you will not need to seed for many years to come unless you get some large bare spots for some reason. Glad you are getting info you can use from my blog postings.

  5. philliprodriguez84 permalink

    Hi Ashton,

    We live on the Chicagoland area and have tried to get a handle on our land for years (paid company..followed my own plan etc…) But never could get lawn to where we wanted to be. From what I understand, the previous homeowner never took care of the lawn for 10+ years and we are paying for their sins…

    Long story short, we just finished following all your steps above and laid Scott’s contractors mix with the starter feed on Saturday and have been watering constantly (weekends) but on weekdays, I have only been able to water heavy in the morning and in the evening when I get home? Will that be a detriment to its growth?

    Also, there is still quite a bit of dead grass on the lawn . We raked 20 bags away (even more pulled away off the grass to decompost) is that okay?

    Sorry for the multiple questions, just want to make sure we execute the project right. The lawn is an eye sore on the street right now but am confident it will turn out all the better!

    Lastly, is there a point when I should throw on more seed if it doesn’t seem to be germibating well?

    Love the site! Always come here for the best lawn advice!!!


    • Hi philliprodriquez84
      Sounds like your new seeding will get enough water to germinate. The seed will germinate best where it comes in contact with the soil. The dead grass on your lawn is not a problem as long as the seed was able to get through it to contact the soil. You should begin to see germination 5 to 10 days after seeding. Keep up the watering schedule for at least several weeks after seeding as additional seed will germinate. Feed your new grass Turf Builder WinterGuard Fall Lawn Food about a month or so after seeding. You can make a wait until the 14 day period to determine if you need to put down additional seed in some areas. Do not put down any weed controls until your new grass has been mowed 4 times. Good luck with your new lawn.

      • Thanks for the quick Response Ashton. I truly appreciate it!

        We will continue with your plan of action and see how it goes!

      • Ashton, If I may..I wanted to ask one more question and I promise no more!!

        I came home this evening and looked through the yard as I began to water and I can’t help but wonder if there is still to much yellow thatch leftover.

        I did two full runs over the yard with a dethatcher from home depot (30+ bags of dead grass for our garabage company on Monday morning pick up) but there is still a decent amount…I am wondering if I should rerent the thatcher, even though I am four days into heavy watering seed/newlawn feed, and tear up the rest…or if there is a thatch decompost concentrate mix that I could spray over spots that are a bit heavier that wont effect the growth?

        Promise no more questions after this:)

      • Mike permalink


        What response did you receive from Ashton on this question?

      • Hey Mike, I never got a response back..So far, the grass is growing in through the yellow spots to some extent..I am worried though that it wont rot away in the future and will just become thick later on.. Saturday will become two weeks and I am going to do another rounds of seeds to fill in the spots…

      • Mike permalink

        My experience has been similar to yours
        After the de-thatching process (on Labor Day weekend) I put down seed and starter fertilizer and, at this time I have plenty of sections of the yard that have no grass growing
        However, it is filling in, ever so slowly, and I am hopeful that time is the most ingredient at this point in the process
        We shall see
        Best of luck in your endeavors

  6. Hi philliprodriquez84 and Mike:
    Sorry Phil I missed your follow up question and Mike I did not see yours until now. The internet connection at my house has been down and I have been attempting to answer questions on my blog from my phone. This has been a bit of a challenge. I am up and running again. The key point from my response to your first question Phil is the seed needs to come in contact with the soil. With a heavy dethatching (which it sounds like you did) this generally happens. The seeds take up to 14 days or so to germinate and as long as you are getting a few seedlings per square inch, you will get great coverage as the grass grows. I would not come back with the thatch machine too soon as this will disrupt the seeding you already have in place. The same with any sprays of weed control. If you know there is an area where the dead thatch is thick and you do not see the soil, these areas could be broken up so you see soil and reseeded before it gets too late (hope for a delay in cold weather). Good luck to you both.

    • Ashton,

      Just wanted to give you an update. Our lawn has come in quite nice. I was worried for a bit (as the above thread alluded too) but its quite green and looks beautiful. I did a second round of seeding two weeks ago, laid winterguard yesterday and continue to water regularly.

      We live in Chicago and expect the first frost this weekend. At the point, should I stop watering? Seprately, should I lay one more batch of winterguard after all the leaves fall in late November?

      Thank you for the guidance. All our neighbors have been blown away. They thought for sure I was going to buying new sod..I sent them to your site 🙂


      • Hi Phil
        Thanks for the update. Glad to hear about your good results. You can begin to drop back on your watering of your initial seeding, especially if your grass is getting an inch of rain (or watering) a week. A rain gauge will help you measure, or a straight sided ice tea glass could also collect water to measure. Your recent seeding two weeks ago should still be kept moist if you can. You can do one more WinterGuard 4 to 6 weeks after the feeding yesterday if your weather stays mild. However, if your weather gets cold enough that you see your grass stop growing and not needing anymore mowing, you could skip the last feeding.

  7. Dan permalink

    Hi Ashton,
    It’s Dan from Charlotte, NC again. I jumped in and blasted my backyard with Roundup about seven weeks ago. Much to my surprise, nothing seemed to be growing back after about three weeks. I ended up raking out as much of the dead stuff as I could then I rented a large rototiller and broke up all the clay. I then dumped 60 bags of Claybreaker soil and 60bags of Scotts Turfbuilder Soil on top. I went over the lawn twice with a lawn roller, put down tall Fescue seed (Heat Tolerant Blue), gently raked it in, then went over it again with the lawn roller. That was three weeks ago now. Things are looking great but here’s my question:

    Every time I have a large area that I am seeding, I have a really hard time judging when is the right time to mow. It seems if I do it too early, the roots are barely developed and the grass pulls out. If I wait too long, the grass tends to fall over and smoother itself (and if I then try to rake it a little to get it stand up, it just pulls out). Is there a general rule of thumb in terms of length, or weeks since seeding until the first mowing? Or, do you have and tips/suggestions for making that first mowing do smoothly? Obviously, I try to tread lightly and take it easy on the turns but in the end, I still have to roll over it with the mow and walk over it myself. Thanks for you help, Dan

  8. Hi Dan
    Suggest you mow when your grass gets to be about 3 to 3-1/2 inches tall and only mow off a half inch or less. Pick a day when the soil is not too wet so you can minimize wheel tracks on your turns. Since your soil is softer now, try to alternate your pattern on your second and third mowing to minimize wheel tracks in the same areas. Glad to hear your lawn came good.

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