You don't need to rototill. It's more work than you need to do, plus it does bring many weed seeds to the surface where they will germinate. Lawn renovation is a big enough job without doing such an unnecessary step.

I am linking you to a good publication from Colorado State Extension on lawn renovation. I looked at the SD extension website, and it's all about farming, so CO would be the one to consult.

Basically, you will kill the lawn, buzz it with the mower, rake up the dead stuff, verticut, core aerate (optional) seed, feed and water. Raking up the dead material will be the most work.

Start the killing process NOW. You want the grass good and dead and decomposing all the way down to the roots by the time you verticut and seed.

I have done this step-by-step process several times myself, turning a weedy field into a lawn. This is the best way, and the least painful.

Here is a link that might be useful: Renovating a Lawn: Colorado State Extension

Well, okay, wonderful. Looking over the CO State document, I see they don't tell you to verticut. That was in the K-State article I had, but that's a PDF without a link.

You need to verticut in two directions, north to south and also east to west. Apply half the seed after verticutting in one direction, and the other half of the seed after the second pass with the verticutter. If you only coreaerate and then seed, you will end up with a lawn that looks like hair plugs. A landscaper did that to us once. That's why I don't hire landscapers anymore.

Thanks!..another question I have is after I kill and rake up the lawn, will the new lawn be strong enough to defend itself from weeds coming back? I am going to use a mixture of KBG and fescue. What exactly is the verticutters purpose? Just so I know what kind of results to shoot for when I rent one.

I appreciate your information!

Can I aerate then verticut? I thought I would kill it, mow it, rake it, aerate it and then finally verticut/feed/seed. Should I lay down fertilizer in between verticut passes with the seed or wait until thats all done and rake it in?

Sorry for all the questions, I just figure if something is worth doing, its worth doing right.

Thanks!

Yes, you can aerate before verticutting. That would actually help to slice up the soil plugs. The purpose of verticutting is to create shallow slits for the seed to fall into, contact the soil and retain moisture. The slits keep the seed relatively in place, unless you get a real flooding rain. So when you verticut in two directions, you initially get what looks like a grid of grass coming up, but it fills in. I go a little crazy with a verticutter and mow in two directions and then do two directions on the diagonal, but I can get obsessive when I work on a lawn.

You can fertilize all at once, after it's all done. That's the fun part. Use a starter fertilizer that contains extra phosphorus for robust root development. Then in mid-November, use a regular lawn fertilizer that is high in nitrogen, a quick release form. The purpose of that last feeding is to get the plants to produce a lot of food resources (sugars) that are then moved into the roots when the plants go dormant for winter. Come springtime, the grass uses those stored foods to emerge from dormancy, thicken up and grow nice and green.

There is really nothing you can do to deal with weeds until the grass becomes established, so don't worry about weeds now. Get the turf up and growing. You don't want to do anything to weeds until you have mowed at least twice, but I would wait until next spring to spray. Young grass plants can be vulnerable to lawn weed killers.

Also, and this is not fun, if you get a dry winter, you need to keep watering the new grass. It will need about a half inch of moisture every two or three weeks just to stay alive. That probably won't be an issue for you, but down here in KC, I have actually had to hook up hoses and water young turf in the winter.

You ask good questions. Don't apologize. And it IS worth doing well, because it's a big job and the seed, fertilizer and equipment rentals are not cheap!

Here is a K-State publication on fertilizing lawns. Most if not all of this can apply to SD.

Here is a link that might be useful: Fertilizing Kansas Lawns

Thank you very much MulchMama!..I now feel more confident in starting this project this weekend. I get a little obsessive when it comes to certain projects myself. More than likely my yard will become my second child. I've got a plan all written up and detailed out, so I'm excited to start.

Thanks again for everything!

Roto-tilling may create a weed problem; that is not the same thing as will, but roto-tilling almost always creates more problems than it cures and makes for way more work.

You're welcome, Joel. I also want to add one more reason not to rototill. The decomposing grass crowns and roots go a long way in keeping your seed in place. We stripped up our whole back lawn a few months after we moved here in 2007 because the yard needed some regrading. Then the area was tilled lightly. We had someone come in and hydroseed all of it. That's a really excellent way of seeding that promotes quick germination and can withstand a decent rain without washing the seed around.

Then we had a two-day deluge, and the hydroseeding slurry washed everywhere, in drifts, into a new "dry" creekbed, into ornamental beds we had just prepped. It was an utter disaster, and it took me almost five years to completely undo all the damage. This is the first year since then that I don't have to do any seeding in the fall.

Wow, I hope this project doesn't turn into a 5 year deal to get it the way I want it! I forgot to mention that my lawn has a slight slope from north to south. Probably about a 12-15 inch difference in height. Is it still ok to verticut in the north south direction or is that too big of a slope? Could this cause the seeds to flow down toward the sidewalk with a heavy rain? Finally, I went out yesterday evening and could easily slide my whole fingers/palm under about an inch of soft soil/roots before I reached firm soil. Is this thatch?..It came right out like a layer of spongy dirt..Should I add in dethatching?..Just curious as to what tools I need to rent. I think now I should start with a dethatcher after it is all dead, rake and clean the area, then aerate..then verticut/overseed..then start with fertilizing and final touch ups...does this sound like a logical way to go about this?

Thanks!

No, just kill it all off and rake it up. The thatch will come along when you rake it. You will have mowed it VERY short, to the point of scalping, so it will rake up. No need to add an extra step. If you would feel better verticutting in two directions, both on a diagonal to the direction of the slope, that would be fine. I would probably do that. Check your longrange weather forecast before you seed -- not that the NWS is all that accurate ten days out, but it can't hurt. If you see a week of thunderstorms in the forecast, plan accordingly!

Our torrential downpour was a real fluke in a very wet year, and it wasn't in the forecast. I was so devastated at the mess I saw developing in the backyard that I just cried and cried. I had just gotten my landscape design certificate, so my husband looked out at the unholy mess out back and said, "Look on the bright side. You could have done this project for a CLIENT!"

The only real way to determine thatch is to cut out a 3x3" square of sod/turf and look at the cross-section. If you see a thickly fiberous top 1/2" or more layer with little soil, that is the thatch. Google "thatch images" to compare.
If you try to slit seed into it, your going to have results you are not going to be happy with. No mater how little thatch you have, slit seeding is going to bring up plant material (it'll look like the lawn is covered with grass clipings). Plan on running the verticle slicer over the whole lawn prior to seeding and rake what is pulled up. One other point. running a slicer over fescue (or rye) seed after it's been sown can damage those larger seeds. Running over KBG seed causes negligable damage and is fine.