7 Steps to Seeding your Lawn
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7 Steps to Seeding your Lawn
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The 7 Steps to Seeding Your Lawn
By Mark Carpenter
This article assumes that you already have an established lawn. Also, this procedure is used for cool season grasses such as, fescue or bluegrass. Warm season grasses such as Zoysia or Burmuda grass is usually not propagated in this manner.
Step 1: Mow & Bag the area that you are going to overseed. This step will clear the area of any debris (grass clippings) that may possibly hinder germination of seed. At this time any other debris such as sticks, rocks or trash should, of course, be removed. I have found that setting your mower at a height of 2 inches will remove most debris, and provide a good clean working surface for overseeding.
Step 2: The next step is to Verticut your lawn. A verticutter is a vertical mowing machine. Its major contribution to this process is to cut furrows into the soil surface, and thus, provide a place for the seed to settle into when the seed is sown. On average, the furrows cut by the verticutter should not be more than an 1/8" to ľ" deep. I say "on average" because most lawns have low and high spots, and it is virtually impossible to get a consistent depth across an entire lawn. When verticutting a level lawn the direction in which you Verticut makes little difference. However, if verticutting on a slope, the direction you Verticut becomes very important. You should always run your verticutter at a 90 degree angle to the slope of the lawn. In other words, if the slope of the lawn runs in a north to south direction, then the direction you should run the verticutter would be east to west. Why?. Think about it. If the slope of the lawn runs north to south, and you put your seed down and you start to pour the water to it or if you get a heavy rain, which way will the seed, lime and fertilizer flow? North to south, correct. If you choose to Verticut north to south, the seed, lime and fertilizer will wash into the north to south furrows, straight down the hill and away from the area intended for renovation. If however, you choose to Verticut east to west, theoretically, the seed, lime and fertilizer will wash into the furrows and stay put. I say "theoretically" because I have in the past, overseeded a lawn, only to have all the seed, lime & fertilizer washed away by a heavy thunderstorm. Believe me, sometimes timing can be everything, just ask that customer.
If you are going to Verticut an irrigated lawn make sure that you flag or mark any sprinkler heads. I have yet to find a sprinkler head that was designed to be Verticut. If you do Verticut a sprinkler head, plan on replacing it and only cry once. Also, on irrigated or unirrigated lawns, flag any rocks, roots, valve boxes or any obstacles that might damage the verticutter and cause injury to either yourself or any bystanders. I have seen verticutters throw rocks and debris hard enough to cause injury and if there is a window in the path of these projectiles, forget it, it will be history.
In the area where I live, you can rent a verticutter for approximately $15 to $18 an hour. If you donít have a trailer to haul the machine, most rental stores will be happy to rent you a trailer for another $5 to $15. Most rental stores have a two hour minimum so you can expect to pay for at least two hours and possibly a trailer rental. This would put the cost of doing your own verticutting at approximately $42. If you follow this 7 step program you will need to Verticut more than once, meaning you will need the machine for longer than 2 hours costing more in rental charges.
A verticutter is not a power rake: A verticutter will remove a minimal amount of thatch, but it is not designed for that purpose. Its purpose is to prepare the soil to accept the grass seed. It may reduce low and high spots in your lawn to a small degree, however, it is not designed for that purpose. It is designed for cutting furrows into the lawn surface and also for knocking the seed into the furrows and covering the seed with just enough dirt to promote germination.
The two machines look identical, however, they are very different.
A verticutter: Has vertical fixed blades that are about 1/8" wide that are made to cut slits or furrows into the soil. Its main function is to be used during seeding and preparing a lawn to accept seed.
A power rake: Has loose, unfixed blades that swing freely and basically beats the thatch out of a lawn. The blades are about 3/16" wide and are designed to remove thatch from lawns. Its main function is to remove thatch from highly neglected lawns that have a serious thatch problem. If the thatch in your lawn is an inch thick, you have a serious thatch problem. Due to my belief that a power rake does more harm than good to a lawn, I highly recommend that you try to remedy any thatch problems through aeration, or at least consult a lawn professional before using a power rake on your lawn.
Step 3: Core aerification. An aerator has vertical tines or blades that will poke holes in your lawn anywhere from one to three inches deep, usually depending on how much moisture is in the soil and on how compacted your lawn is. A core aerator pulls plugs up from the soil and distributes the plugs on top of the lawn. By leaving the plugs on top of the lawn the nutrients in these plugs will now be recycled to your grass. This is a good thing. These plugs are often considered an eyesore, however, they usually decompose in a period of 2 to 3 weeks. The addition of soil (plugs) to the thatch layer in your lawn will also promote faster decomposition of the thatch layer.
Getting oxygen into the soil so that the plant can use it to make food through respiration is the most important benefit of core aerification. The roots of a plant use oxygen during respiration to make food:
C6H12O6 + O2 ---> CO2 + H2O
The holes created by the aerator makes available oxygen to the microbes (and the roots of the turf) that are required for a healthy and vibrant lawn. If your lawn is compacted, it probably means that the microbes (that break down nitrogen, that make it possible for your grass to use the nitrogen) are oxygen starved. By getting oxygen into the soil, you encourage the growth of these microbes and, therefore, the growth of the grass in your lawn. These microbes are also responsible for the decomposition of the thatch layer in your lawn. Promoting the growth of these microbes is one of the most important functions that aerating your lawn can provide.
Another benefit derived from core aerification is the reduction of compaction in the lawn area. Have you ever tried to grow grass in an area of your lawn where there is a lot of foot traffic, or where your dog runs up and down a fence line or even worse where someone parks his car on the lawn? It canít be done, because the soil is just too compacted. Aerification (while probably isnít going to grow grass on somebodyís makeshift driveway) will increase the chances of getting grass to grow in high traffic areas of your lawn. Even in low traffic areas of your lawn, think of the things that promote compaction. For instance, someone walking on the lawn while they are mowing, if you mow your lawn 25 times a growing season, the compaction adds up. How about during the winter when we get 12 inches of snow on our lawns? Just the weight of the snow on top of your lawn could be enough of a reason for aerating your lawn.
Another benefit from aerification is that as the aerator pokes holes in your lawn it cuts grass roots, rhizomes and stolons which in turn generate more grass, which in turn increases grass density. Also, as the new grass seed falls into or washes into these holes it gives the seedlings an excellent spot to germinate. Along with the seed, lime and fertilizer will fall into these holes, which will hasten the incorporation of these lawn enhancing amendments into your root zone.
Obviously, core aerification is not something you do only when you are seeding your lawn. I core aerate my own lawn twice a year, once in the spring and then again in the fall (Sept.) when I seed my lawn. With the wind blown clay soil we have in the Kansas City area which compacts so readily, most lawn companies recommend aerifying twice a year. If you donít notice any difference immediately, donít be discouraged, it may take several years to reap the benefits of core aerification.
Step 4: Mow & bag your lawn again. However, set your mower height up one inch so you donít remove the plugs that the aerifyer has put on the surface of your lawn. The mower will also (hopefully) break up some of the plugs that the aerator has left on the surface of the lawn. Mowing & bagging your lawn will again remove any grass clippings or possibly any thatch that the verticutter may have deposited on the surface of your lawn. This will give you a clean surface to work with for the next step, which will be seeding the lawn.
Step 5: Seeding the lawn. What kind of seed should I use? In the Kansas City area on unirrigated lawns there really is only one choice of grass seed. Tall turf type thin bladed Fescues. Why?
What about Bluegrass? Bluegrass is not a native grass to the Kansas City area. Our environment does not lend itself to Bluegrass the way it does Fescue. However, if you have an irrigated lawn and are willing to pay the water bills that will come with a Bluegrass lawn and if you are willing to put up with the diseases (fungus) that come with excessive watering during June, July and August, then I say go with it. Otherwise, I say go without it. Donít get me wrong, a nice Bluegrass lawn is as attractive a lawn as you can get. Bluegrass has long been a highly recommended grass to grow in this area because of its aesthetic qualities and will continue to be so. However, for the average homeowner, it may be considered to be too much of a high maintenance grass to grow in this area.
Zoyzia & Bermuda grass? These grasses are warm season grasses and they look great during the hot summer months. On the other hand, the rest of the year, they look somewhat less than attractive. If you wish to cultivate these grasses in your lawn, they are usually plugged or sodded.
Below, I have included a Grass Evaluation Chart with this handout which, should give you an idea as to what grasses do well under certain specified conditions for the Kansas City area.
Step 6: Fertilizer. At this point, apply a starter fertilizer. The combination I use usually hovers around a 18-24-12. This combination of nutrients is low in nitrogen and high in phosphorus and potassium (potash). Nitrogen promotes growth of the leaf blade of the grass, while phosphorus and potash promote Crown and root growth. Be careful not to use a fertilizer with a high nitrogen content. Too much nitrogen could possibly chemically burn the new grass seedlings. Make sure that the fertilizer you use does not contain a preemergent. (In other words, don't just go into your garage and use the same fertilizer you used last spring. It's very likely to contain too much nitrogen and probably a preemergent. As we all know, preemergent will prohibit the germination of grass seed.)
Step 7: Verticutt your lawn again. If possible, Verticut at a different angle than the first verticutting ( preferably at a 90 degree angle to the first verticutting ). This second verticutting is done to knock to grass seed into the furrows that were created by the first verticutting. The second verticutting will also cover the grass seed with just a little bit of soil, this is exactly what you want. If the seed isn't covered just a little bit with soil it may not germinate. Since verticutting is such a labor intensive part of the seeding process, many homeowners have a tendency to skip the second verticutting. Having done a lot of verticutting myself, I can certainly understand just where they are coming from. However, resist this temptation, you've gone this far, let's do it right, and go all the way. You will reap the benefits later on down the road by having a nice lawn.
One last thing, and probably the most important.
How much should you water?
The general rule of thumb is to keep the ground moist for at least two to three weeks. Never let the seed dry out. If the seed dries out it could possibly die. Do not over water. Too much water at one time, and the seed will wash away or wash into low spots in the lawn. You will wind up having lots of grass in the low spots and none in the high spots. Depending on how hot the weather is, usually watering every other day is sufficient to provide the seed and seedlings with enough water so that they will survive to reach maturity. If we are in a dry spell, keeping the ground moist is the most important thing you can do to promote a successful seeding procedure.
If you have any questions about seeding your lawn, please feel free to go to the Gardening Q & A page of this website and submit your questions.
"7 steps to seeding your lawn" was written by
Mark Carpenter: Master Gardener and Owner/Operator of The Lawn Ranger.
Doing business in the Kansas City area for 15 years.
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