Spongy Lawn? Thatch, Drainage Or Something Else


Walking into work one day I step on the grass, and my foot sinks slightly into the ground but with no squish. This is definitely a feeling I was not used to so I bent down to investigate. As I press my hand into the grass I get this spongy feeling, I grabbed a handful of the brown dead grass and pull, tearing out some healthy grass in the process. I didn’t know what this was at the time so I decided to find out.

A spongy lawn is usually caused by an excess layer thatch normally between 1/2 to 1 inch thick. Other possible causes include poor drainage, usually associated with a squishy feeling, or a digging animal infestation, usually associated with loose mounds of dirt built up around the lawn.

If you’re dealing with one of these issues it’s important to find the solution and fast. Any one of them could kill a portion or your lawn or the entire thing within a matter of months. Let’s look at how to identify problems you’re facing with your lawn and then how to solve it.

Thatch, Drainage or Animals

The first step in this process is a little detective work. Below we will talk about the different indications you can expect to see depending on your situation. Just know that whatever your problem is, putting it off will only make matters worse so let’s dive In.

Thatch is normally described as a spongy layer above the soil. It is comprised of dead grass clippings compressed directly above the soils surface. Once the thatch layer gets to about 1/2 inch thick it begins to feel spongy.

You may ask yourself, I thought that leaving grass clippings on the lawn was healthy? While this is true, excessive plant matter covering the ground can limit water, fertilizer, sunshine and other nutrients from reaching the soil. This limits the growth of the existing grass and inhibits new grass from sprouting. It can be almost impossible for the fungi and bacteria to keep up with the large amounts of dead grass piling on top of it.

To confirm that thatch is your problem, the easiest way is to take your spade and dig the same hole you would for planting approximately three inches deep. By looking at the cross section of the soil you can see how thick the thatch layer is. If the thatch is greater than 1/2 inch (approximately the distance tip of your thumb to your first joint) then this may be the cause of your browning and dieing grass.

If your spongy layer can also be described as squishy then your yard may not be draining properly. The key difference between this issue and excessive thatch is the presence of water. This does not mean that you won’t have thatch on your lawn but merely that yard drainage maybe the main issue since a small amount of thatch is not bad, but healthy for your lawn. If you think this might be your issue then you may want to read this article about different types of drainage problem solutions.

If running water is damaging or eroding the earth beneath your lawn and your soft the dirt continues to get lower and lower, you may have severe erosion beneath the surface and a possibility a small sinkholes developing in your lawn. If you are concerned with this and want to know more than check out his article about what sinkholes are and what causes them.

The next possibility is animals, and the good part about this is that it is much easier to take care of and won’t kill your grass if the problem is not solved immediately. This article gives examples of common pests that dig holes in your yard. It also will help to identify which one it is and guide you in solving your problem.

Everything from gophers to moles and insects digging holes large too small can cause your soil to get softer or looser. Getting rid of these pests can be as easy as putting down a simple product application and can work within the day or can be a constant battle that is fought year after year. When push comes to shove you may need to consult a professional to determine the correct path moving forward. The last thing you need is having someone come knocking on your door to find you for hurting an endangered wildlife species.

Thatch: Good or Bad

Thatch is good by nature, as dead plant life decays into needed nutrients for the soil. A healthy amount of thatch is 1/2 inch when measured from the soil to the top of the Dead layer of grass. Thatch can be created either by the natural death and decay of grass or buy lawn clippings left behind after you mow the lawn.

Different ways to keep thatch at a healthy level in your lawn is to only leave fresh cut lawn clippings in the grass. If you can see the dirt through the grass then you should leave it. If you can already see a layer of dead grass in the lawn you can either use the bag that comes with your mower or a rake to reduce the buildup of thatch in specific areas.

A good way to dispose of thatch or lawn clippings is by composting them in an out-of-sight space on your property. This dead plant matter can become gold with time creating a nutrient-rich environment for both in-ground and potted plants. While it is definitely recommended to place excess lawn clippings in a compost pile to recycle them, you can also dispose of them in the trash or burn them depending on the laws of your state.

The bad part about thatch is when it is allowed to build beyond the capacity of the bacteria and fungi on the ground that decompose it. “ If decomposition could not occur the nitrogen in dead organic matter would remain locked up and plant growth would decrease over time as the nitrogen the plants took from the soil was not replaced.” says the Utah State Department of Biology.

Bottom line, thatch can be good for your lawn or bad depending on the amount of thatch produced by your lawn and how it is managed. Just like Mom said too much of a good thing can hurt you… Or your lawn.

Dethatching Your Lawn

Dethatching your lawn is a 7-step process and to be honest its either backbreaking labor or slightly less backbreaking labor. Before you begin your dethatching process, doing a weekend’s worth of manual labor may not be your only option.

The cost of dethatching hovers somewhere around $200 to $400 per thousand square feet. With the average lawn size hovering a little over 10,000 square feet (provided by our trusty homeadvisor.com), that puts the average homeowner paying between $2,000 and $4,000 just to dethatch a lawn. For those of you without 5K under your pillow renting a power rake and doing some amount of manual labor could save the day.

Buying the hand tools and renting the power tools necessary to dethatch your lawn will seem like chump change when compared to having a professional come in and do it. Below you will find a short list of all the tools that you will need, and a ballpark cost of what you can expect to pay for all of them.

  • Renting a Power Rake for the Day – $70-$90 (see prices in your area)
  • Buy Dethatching Rake – $50
  • Contractor Bags – $35 (You may have extra and this purchase is not absolutely necessary…look below)
  • Time – Priceless

Now, let’s get down to business as one of my favorite Disney movie songs says. First step is to mow your lawn. If you have a lawn mower this is easy, but if you pay for a lawn mowing service just coordinate ahead of time so that you’re not asking your lawn mowing service to mow on a day that’s inconvenient for you.

Remember, if you have a lawn mowing service you can simply ask them to take the clippings away or dispose of them in the woods for you rather than leaving you extra work.

Step two is to take out your power rake. On average I adjust the blade settings too high and three inches apart. For the majority of grasses this works, but the tougher the grass the lower and closer together you set your blade settings. Go over 2 to 3 feet of lawn at the highest setting, then adjust your settings to be lower and closer together. Mow over another area, and repeat this process until you’re tearing up the roots of the grass. Move your setting back one Higher and wider and this is the setting you will use to dethatch the rest of your lawn. If you’re having trouble with this part take a look at this video to help you walk through the process.

Once you’re done power raking your entire lawn it is time for the next step. Step three clear out all the loose thatch. using your hand rake collect it into convenient piles off of the lawn to dispose of later. A quick tip is to rake it onto a tarp so that later, when you move it or dump it, you can easily pull the tarp across the lawn to your compost pile, truck bed or anywhere else.

Step four is similar to step 2, but you will power rake the lawn perpendicular to how you did it last time with the same setting. This is to ensure equal removal of thatch as raking again in one direction might only slice through the same paths the blades cut through before.

Step 5 is again the same as step 3 to rake it away and clean it up. If you have a little helper this is an easy way to delineate work as several people(my kids) can do it and it does not require the operation of a potentially dangerous power tool.

Step 6 involves manually dethatching spots in your lawn that require more attention. Why don’t you just go over that area with the power rake? It is because of how the power rake does what it does. Every time you run over your lawn with a power rake your grass is being pulled and torn. For severely thatched lawns this is necessary, but for the same reason we limit our dethatching height, we limit the amount we dethatch specific areas.

Step 7 is for your final clean up. Rake out that last bit of debris and get rid of it however you choose too. If you have a composting bin/area than that is a good idea, but if not then it will probably mean a trip to the dump. If you do fertilize your lawn or cultivate for gardening and you have the space, composting is an investment that you can make now that will definitely more than pay for itself later(its free by the way).

Now that we are done, sit back, get a drink and enjoy the view as your lawn is probably quite a bit more green than it was a few hours ago. If you are a little discouraged that grass is so much more sparse than you were expecting then we have ways of fixing that too.

Repair Your Lawn And Prevent Thatch Buildup

Now we are in recovery mode. Your lawns wound is fresh and you can choose to let it scar over or put the antibiotic and gauze on it to help it grow back bigger and better than ever. You are now letting moisture, air and needed nutrients into the soil which means you have the perfect path to give your grass everything it needs to thrive.

If you are dealing with pooling water in your garden beds instead of your lawn than check this article out to find a way to fix it.

Aerate! Oh yeah, lets poke some holes into that lawn. Aerating will provide more oxygen to the soil and loosen it up. Sometimes a lack of water absorbing into the ground can dry it out severely and you may find it rock hard.

Fertilize! Give the seed you are about to put down a warm welcome by providing it the required nutrients before it is even there. This allows you to place the seeds into an environment that will help it grow from the start.

Seed! Give the lawn everything it needs. Although some types of grass repair themselves easily like Kentucky Bluegrass, by seeding your lawn you are giving the weakened grass the reinforcements it needs to take back its property by storm. This will also help the grass take root before weeds can move in giving you just another problem.

Water! Finish it up with a little drink for not just yourself but also your grass. Don’t over water however because watering too heavily after fertilizing can wash away nutrients that you just put there. Make the top inch or two damp and then continue watering approximately twice a week only skipping if it rained.

Preventing thatch buildup just involves removing the grass clipping when you mow and using the manually dethatching rake that you just got to periodically go over your lawn. Because of the hard work you are doing today you will reap the rewards over and over. You can do it!

How to compost?

What is causing holes in my ground?

Manny Moore

Getting my hands dirty and building a place that me and my small family love is a driving factor for what I do and how I do it. I want to share what I have learned and practiced so that it is just that much easier for everyone to have another tool in their tool belt. Your home should be a place that you love and feel comfortable in and your backyard should be no different.

Recent Posts