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  • Writer's pictureJanae Moss

Lawn Dethatching

A lawn dethatcher is also referred to as a power rake, a lawn sweeper, a thatching machine, or a dethatching rake. All of these have the same purpose, which is to remove undesired thatch out of your lawn. Thatch is another all encompassing word which essentially means any unwanted material in your lawn such as dead grasses and mosses. It can also refer to dead sod, undesirable grasses and creeping lawn weeds. It takes the longest to dethatch thick moss and dead sod. Lawns with really thick moss may need to be dethatched several times.

A lawn dethatcher machine usually does a better job than a lawn mower dethatching blade and is a lot less time consuming then a dethatching rake. A lawn dethatcher machine works by having 4 sets of raking blade spinning vertically and hitting the surface of the ground at a perpendicular angle. The pulley on the engine spins the blades. It works like a brush combing snarls and thatch out of the lawn, but leaving the grass in place. Any good dethatcher will have a level that can engage and disengage the spinning blades.

The benefit of removing thatch with a lawn dethatcher is that it can improve the overall look and health of the lawn. Weeds and moss that choke the lawn off from water and sunlight can be eliminated. Most rental shops rent lawn dethatchers. They rent for $35 to $80 depending on where you rent and the length of the rental. You may need to ask for a power rake or lawn sweeper but don't worry they are the same thing. It is just that every brand calls it their own name. If you do it your self be careful with going over roots, rocks and sprinkler heads. A lawn dethacther is about the size of a lawnmower, only is about twice as heavy and as powerful.

How to Dethatch a Lawn and Lawn Dethatchers

§ Determine if your lawn needs to be dethatched. Power lawn dethatchers are stressful to your grass and should only be used as needed. Take a sample of grass and soil and measure the spongy layer of thatch in-between that is made up of organic materials such as grass clippings, pine needles, leaves and roots. You may want to test several different areas since the build-up can vary. If it is a half an inch deep, think about dethatching soon. It is definitely needed if it is an inch or more.

§ Decide whether to rent or borrow a power dethatcher or hire a professional to do it for you. Lawn dethatchers look kind of like power lawn mowers but are typically much heavier and have several vertical tines that cut into the thatch layer without ruining the grass. Because you want to have the blade height and spacing just right, it can be a bit tricky to use if you are not used to them. You should be able to do a typical lawn in a half-day rental period, which will cost about $60-80 dollars or around $100-$125 for 8-hours if you have a larger lawn.

§ Plan to dethatch at the right time. You do not want the soil to be too dry or too wet. Since it is hard on your grass, there needs to be recovering time, at least two or three weeks of active growing season before the weather gets too hot and dry or too cold. Typically early spring or late fall are best.

§ Prep your lawn and gather other lawn care materials. You want to mow your grass about half its normal height. If you want to overseed (a really good idea), fertilize (a good idea) and/or topdress (not necessary but a benefit to many lawns and many help even it out) have those materials readily available.

§ Set-up the thatcher. When you go to pick up the lawn thatcher, have the rental center help you set blade height or spacing. For warm weather grasses, the height is set to cut into the turf about ½ inch with the blades 1-2 inches apart. Since cool weather grasses are thinner, blade spacing can be increased to 3 inches and the height can be set around ¼ inch. As you are dethatching, you can make small adjustments if they are needed.

§ Go over each area more than once. For the best coverage and results, make several crosswise patterns in each area. Consider using a manual dethatching rake to get to the corners and get up additional moss.

Why is Lawn Dethatching Necessary?

If you want to have a beautifully maintained lawn, it is important that you do the necessary tasks such as lawn dethatching. This task is considered as a significant part of lawn care and maintenance because it will help get rid of the various layers of dead plants and grass that exists in your lawn. The reason why dead plants need to be removed is because they can stop nutrients and water getting to the roots of your plants. At the same time, they can also act as the breeding ground of various diseases for your lawn that have the tendency to quickly spread out. If you are going to dethatch your lawn, it is recommended that you leave a small area of thatch left untouched. This is because it will help protect grass against heat stress as well as drought. A healthy lawn will normally have a half inch thick of thatch layer. In order to know if it is time to do a lawn dethatching, you can dig up in your yard and measure how thick the thatch layer currently is. Once it is beyond half an inch, that's the time you can dethatch your lawn.

The best time to dethatch your lawn is during the fall. This is because doing this task in the spring months can add more damage to the crowns of grass that have just grown. Here are some useful tips that you can use when you do lawn dethatching:

§ Mow lawn equally low.

§ A hand rake should be used in smaller areas.

§ Make use of a core aerator.

Once there is a serious buildup of thatch and it causes a severe problem, renting or hiring a professional lawn care company is recommended. This can also occur once the thatch is over an inch thick. For this, a professional lawn dethatching company is advised since they will use mechanical equipment on your lawn.

How and When to Remove Thatch From Your Lawn

You Should Consider Dethatching Your Lawn if:

1. You have a lawn comprised of cool season grass or grasses, the most common of which are perennial ryegrass, Kentucky bluegrass, and fescue. Cool season grasses grow where the winters are colder; they spread by producing underground rhizomes.

2. Your lawn has spots where the grass is very thin - where the individual grass blades are weak and far apart from one another.

3. Your lawn has large brown spots where the thatch is so thick that it has temporarily suppressed all of most of the grass plants in that area of the lawn.

4. Water runs off your lawn before it can penetrate the soil. This is especially problematic on sloping areas, where thatch prevents a barrier to water absorption.

5. Your lawn is severely compacted by heavy foot traffic, and you are planning to aerate it, or have it aerated professionally. (Thatch build-up should always be removed before aerating a lawn.)

6. You are planning to over seed your lawn this fall (which is always a good idea).

Timing - When to Dethatch

Timing is very important; you can actually do more harm than good if you dethatch at the wrong time. The very best time to dethatch a lawn is early fall, at least four weeks before the end of the summer/fall growing season. An early fall dethatching can prepare your lawn for over seeding and fall feeding, giving it the best preparation for surviving the winter and rebounding quickly the following spring. Late spring, after several weeks of green grass growth, is the second best time to dethatch. Of course, if you dethatched the previous fall, you won't need to dethatch in the spring. There is virtually no thatch build-up during the winter.

How Important Is Lawn Thatching With a Thatch Rake?

Lawn thatching is very important if your lawn contains a lot of buildup. Lawn thatch refers to the layer of dead grass or moss that is growing in your lawn. You can do lawn thatching with a thatch rake or a thatching machine. This can also be done to improve the look good lawns or lawn that are spare. (Although these lawn will also need overseeding.) How often your need to be thatched depends a lot on the quality of grass you have and what other stuff might be growing in your lawn. There are several benefits to thatching a lawn.

Some of the most important are as follows:

§ Dethatching gets rid of harmful build up. This build up can block water, air and sunlight from reaching the plants or the roots. The barrier it creates block oxygen witch breaks down the thatch. This is why sometime thatch can become really bad on year, when the lawn reaches a tipping point and it produces thatch faster than it consumes it.

§ This activity also aides in reseeding. This is because it opens up the ground all the way to the dirt to allow overseeding. In addition, it creates loose furrows and loosens the dirt on top of the lawn to help the seed to grow in faster. In addition, it can trim existing plants allowing more soil space to receive new sunlight and allowing more grass seed to come in. The result is thicker turf.

§ Also another benefit is the lawn dethatching helps to remove the thatch layer where a lot insects live. Although most insect don't eat the thatch, they do build their homes in it. The Thatch layer keeps them warm in the winter and protects them from predators during the rest of the year. A lot of times regular thatching will do a lot to prevent insect infestations.

§ Thatching your lawn can also help to get rid of weak grass pants. When you overseed, you can replace this with new, healthier plant, or at least ones that will grow in the shade.

§ Lawn thatching helps to scarify the soil and make it ideal for planting. Grass only need about 1/8 to ¼ inch of loss dirt to germinate. Thatching before you overseed dramatically increases germination rates.

Dethatching vs. Core Aeration

Of the two solutions, dethatching is certainly preferable to core aeration because core aeration requires a mechanical device. Unhappily, you may not have a choice. The severity of the situation determines which solution is implemented. Dethatching is for mild cases. You will know afterward that it worked if your grass starts looking better the following year.

If grass health does not pick up, that could mean that you have a more severe case. Core aeration may be necessary for your lawn. It is best performed in fall. If you have badly compacted soil, that is another reason to aerate your lawn.

You have three options when it comes to core aeration:

§ Hire a lawn service to do the job.

§ Rent a core aerator.

§ Buy an aerator.

The average homeowner should be able to either hire a lawn service or to rent a core aerator. When it comes to buying, not only is cost an issue but so is storage. Dethatching a lawn by means of a core aerator is probably not going to be a yearly task. Whenever it is not in use, this large piece of equipment will be taking up space in your garage or storage shed. An exception might be made if you own a tractor or a riding lawn mower because you can buy an attachment for these machines that will allow you to aerate your lawn.

If you are not physically up to the job, do not live near a rental center, or just plain do not like gadgets very much, it might make sense for you to choose to hire a lawn service to do this work. Otherwise, renting is a great option.

Truco Services, Inc.

4640 Commerce Drive

Murray, Utah 84107

(801) 466-8044

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