Lawn Care: Overseeder – How To Use an Over Seeding Machine

posted in: Rants 9

Are Overseeders Necessary?

Learn how I got excellent results, thick and healthy turf, and what I learned when I rented an Overseeder machine. Seed your lawn the right way, and find out what you need for this project.

I’ve always tried to overseed my lawn by first aerating, then mowing low, then going over the lawn with a broadcast spreader. I now realize that’s a wasteful, ineffective way of doing it.  Over-seeding the right way means using an Overseeder machine.

What You’ll Need for the Overseeding Project:

  • Rent an Overseeder Machine – I rented a “Billy Goat” brand model
  • Transportation – This machine is larger than a push-mower, so you’ll need a pick-up, SUV, or roomy hatchback
  • Buy Grass Seed – I recommend at least 5 lbs. per 1000 sq ft. of sparse lawn, or at least 3 lbs. for a maintenance seeding
  • Water – Get a good sprinkler that will cover an appropriate area, and that is adjustable (they’re inexpensive)
  • Lawn Mower – Mow shorter than usual before over-seeding (hopefully you usually mow at least 4″ tall)

When is the best time of year to over-seed?

Typically, Spring or Fall.  I overseeded early Fall (late September) in the north Midwest: Iowa.  I saw decent results before the frost came, but I was a little disappointed.  Now, after the long winter, by mid-Spring I am surprised by how thick and healthy the turf is.  I haven’t even fertilized since last Fall.

I’m sure you’ll still get results if you overseed in the Summer, providing you water the ever holy piss out of your lawn for 2 months or more afterward, but grass often wants to be dormant in the Summer months.

Preparation: Let’s get ready to overseed

I decided to overseed last fall after a wet year when we got so much rain that much of the turf in my front lawn drainage ditches died.  First I plug aerated (see this article for more on lawn aeration) and then waited a couple weeks for the plugs to get broken up by mowing and worked back into the soil.  Then I mowed shorter-than-usual so the grass wouldn’t be overly thick and tangled for the Overseeder machine.

If your lawn is really dry, I recommend spending a day or two watering it very heavily to soften up that first inch of topsoil.  An over seeding machine is basically a “verticutter” with a hopper on it.  These vertical cutting blades will “fight” you less if they can more easily cut grooves into your lawn’s surface.


This part is up to you.  I called my local equipment rental store and asked if they had over seeder machines for rent.  It cost somewhere around $65/4 hours or $85/day.

Here’s a tip I usually try to employ when renting equipment:  Rent on a Saturday.  Often rental businesses aren’t open on Sundays, so you can pay for 1 day (Sat.) but then keep it Sunday at no additional charge, returning Monday morning.  I don’t do this to be underhanded, I do it when I’ve never used a piece of equipment before, and I’m insecure about how long a project will take, or what unforeseen issues may come up to add time to the process.  If I’m comfortable with a project (experienced), then I know how long it will take and can rent accordingly.

Remember:  if you don’t have a vehicle that can accommodate an overseeder, borrow one.

Grass Seed:

I live in Iowa, an agrarian region, which can be helpful for finding lawn care materials at bulk-prices.  But if you live in the U.S., it shouldn’t be hard to find decent deals on grass seed no matter where you live with a lawn.  I bought 50 lbs. of grass seed in mid-September for about $35 from a corn & soybean dealer who didn’t want a couple bags of grass seed sitting in his warehouse all winter.  The mix was 75% Fescue, 25% Kentucky Blue Grass.  I was weary of this mix as fescue can be more temperamental in my region than bluegrass, but it worked out fine.

How much grass to purchase?

Just remember, if you’re going to spend the money to rent the equipment, don’t cheap-out on the amount of seed you buy.  Buy at least 5 pounds per 1,000 square feet.

This is easy to figure:

Roughly measure your home’s lot size.  Usually a lot is rectangular.  For example; If your lot is 100 feet x 150 feet (just guesstimate) then you have a 15,000 sq ft lawn.  Now minus the footprint of your house and other buildings or landscape features.  If your house is 75 ft x 30 ft, then you have about 2,000 sq ft to take from the 15,000 sq ft lot size.  I would minus out an estimate of your driveway, low evergreen trees, etc.  We’ll call it another 3,000 sq ft.

Lawn Square Footage Example Calculation:
15,000 Lot Size
– 2,000 House Footprint
– 3,000 Other Stuff (driveway, landscaping, low bushes..)
= 10,000 square feet
÷ 1,000 (figure out how many units of 1,000 square feet you have)
= 10
x 5 lbs Grass Seed
50 lbs of Grass Seed Needed for this example

If you really want to get an accurate measurement of your lot and house size, you may be able to find the information on your county or municipality’s Assessor or Property Tax website.  I can find my lot and use a “tape measure” tool to measure the property.  Here’s a screenshot of the satellite map I found:

Aerial Satellite Photo - Measure Lot Square Footage
Aerial Satellite Photo – Measure Lot Square Footage

One more thing about grass seed; It’s important to get enough because you may not understand what setting to put the over-seeding machine’s hopper on at first (I didn’t).  I read the instructions on the underside of the machine’s hopper lid, but those recommended settings were too liberal.  I soon realized I had sewn about half my seed on less than 1/3 of my lawn.  Try to go easy at first, start with a low setting of seed dispersion.  You can always go back over an area later, and it’s actually recommended you do – so go across the lawn in one direction, and then go across in another direction to make a crosshatch or checkerboard pattern.

Operating the Overseeder Machine

This is tricky at first.  Here’s what you want to be happening when you operate this machine:  it should be pulling you along!  There’s a knob or lever on the machine to set the depth of the cutting blades.  You want them to go about a half inch or so into the topsoil.

If it doesn’t feel like you’re being pulled by the machine, it probably means it’s not digging / cutting into the ground so there’s no friction and forward propulsion other than the motorized wheels.  Also, unless you’ve got an abnormally well graded and homogeneous lawn, there’s all sorts of small hills and valleys to consider.  This machine won’t hardly touch the soil surface in the micro-valleys, but then suddenly lurch forward as it grabs and tears into a micro-hill.  Don’t worry, you’ll get used to it.  You should go over your lawn twice anyway, so you’ll be an old pro by the second time around (providing you haven’t used all your seed up by then).

In sparser areas of your lawn (mostly dirt and dead turf) you should be able to see the grooves that have been cut for the seed to drop down into and get forced into by the machine’s blades.  In thicker-turf areas, you may not see grooves so much as evidence of de-thatching, meaning the machine is cutting through the normal mat of dead vegetation and kicking up tufts of fine straw material here and there.

Lawn Overseeder machine - the best way to get thick, healthy turf grass
Lawn Overseeder machine – the best way to get thick, healthy turf grass

Time to Water, Water, Water Some More…

This is no joke.  There is no short-cut.  It must be done, otherwise you’re wasting your money and time on all the other stuff you did.  Every day that it doesn’t rain, you need to soak your lawn.  You need to get home from work and start in one corner of the lawn, start your sprinkler, let it go for a half-hour or more, then move the sprinkler to the next area of your lawn.  Every Single Day for At Least One Entire Month.

If you’re not lucky enough to have a built-in sprinkler system, get a lawn and garden rotary sprayer that can be adjustable to spray within a certain area (instead of just full 360°).  I bought one at my local big-box home store for only $6 or $7.  I assumed it would break immediately at that price, but it’s been surprisingly rugged, and extremely helpful.  I recommend it because of its range and adjustability.  Mine looks a little different from the photo, but I believe it’s the same manufacturer; Nelson.

Nelson brand - adjustable rotary lawn and garden water sprinkler

Nelson brand – adjustable rotary lawn and garden water sprinkler

What Happens Next:

  • In 5 to 12 days you’re going to start seeing your little baby grasses coming up.  Keep watering, make sure they take good deep root!
  • After your short grass gets tall enough that you feel comfortable mowing it, go ahead and raise the height of your cutting deck to at least 4″.  The higher you mow, the better your lawn looks, the healthier your turf will be, and maybe you’ll win the Lottery, too.
  • If your experience with over-seeding is like mine, you may not notice the full effect for many months, if not a year.  Be patient and your reward will come.

Anything Else?

If you have questions or I forgot something, comment and let me know.  Happy Lawn Care!

9 Responses

  1. bonniesplants
    | Reply

    Are all the machines self propelled or are some more “work”?

    • Kris Bunda
      | Reply

      Hi, sorry I missed this before. They’re **Kind Of** self propelled, because they’ve got these blades that dig in the ground and **May** at time, help propel the machine forward. In fact, sometimes it tries to run away. Other times, they may dig too far into the earth in certain spots and make it very difficult to move it forward. I have never used self-propelled overseeders, but I know they exist.

  2. jja
    | Reply

    This was hilarious – and helpful at the same time! Thank you!

  3. Keith
    | Reply

    When should you fertilize? I put down bug killer/fertilizer every year. When can I do that?

    • Kris Bunda
      | Reply

      Sorry Keith, I’m not an expert on fertilizing or bug killing. But I think it’s good to spread some fertilizer granules on the lawn you’re overseeding, just make sure they’re not the “Weed ‘n’ Feed” type, because the weed-inhibitor part of that equation will inhibit your grass seeds from germinating.

  4. robert s saville
    | Reply

    Keith, i would recommend applying some lime and starter fertilizer at the time of aeration. After a week, overseed the lawn.-Robert

  5. rumisharice
    | Reply

    i have mostly dirt and very little grass now, will this work for me too?

    • Kris Bunda
      | Reply

      Do you have hard-packed dirt or freshly grated, healthy topsoil dirt?

      If you’ve got old, hard, baked and packed dust, then you probably need to get a load of topsoil or do some work to it. But if you’ve got a lot of fresh dirt (because maybe your house is new or a lot of work was done on your lot and everything got tore up), you can do overseeding. You probably want to wait until it dries out some, because it’s hard to push overseeders through wet dirt, makes a mess. But it does a good job of evenly impregnating and coverage.

      Or if your dirt is really well tilled and healthy, can probably just use a broadcaster. If you have and pitch/hills on your lot and it’s mostly dirt, you should probably spread some newspaper or straw liberally around to cover the seed while it germinates. This retains water, makes it more difficult to wash away/erode, and maybe keeps some of it from being eaten (do birds eat grass seed? I dunno).

      When I say newspaper, maybe you can get a bunch of shredded paper to cover the ground–I don’t know if that’s a good idea or if paper has chemicals that screw up ph balance or something… but I’ve literally spread whole sheets of newsprint on the ground before and then they get wet and become part of the earth, but also kind of hold the seed to the ground like a Papier-mâché project. After while, the grass germinates, pokes through the paper, and the paper dissolves and disappears. Sometimes you have to get something to hold your seed to the ground, and moisture around the seed.

      That’s my amateur advice.

  6. Negron
    | Reply

    While some people need to do the work themselves to save money especially during these hard hitting economic times but for me its the great sense of accomplishment I get knowing I did all the work myself when I look out my window and see my great looking lawn. The old pioneer spirit I guess!

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