When & How To Dethatch Bermuda Grass
Last updated: 8 March 2024
Bermuda grass, a perennial, warm-season grass, is characterized by its vigorous growth, adaptability, and toughness. Due to the vigor and creeping nature of the grass, a Bermuda lawn is prone to thatch accumulation. A little thatch is good for your lawn, but when the layer becomes too thick, dethatching is necessary to maintain the lawn’s health and aesthetics.
For best results, it is recommended to dethatch your Bermuda lawn in mid to late spring. Avoid dethatching your lawn in the summer when temperatures exceed 90 °F or during the cold season when it is dormant.
When timed and performed correctly, dethatching improves the overall health of your lawn and makes it greener and fuller.
A thin thatch layer of ½” thick or less is good for your Bermuda lawn. The thatch suppresses weed growth, conserves water, and insulates your lawn against harsh weather. Thatch also protects your yard from injuries caused by high impact or traffic.
However, if the thatch layer exceeds a thickness of ½”, it can choke the grass by blocking water, air, and nutrients from reaching the soil. Thick thatch can also encourage pests and pathogens and expose the lawn to scalping.
If you notice that your Bermuda lawn has accumulated thatch, dethatch it to maintain and boost your lawn’s health. But when is the best time to dethatch Bermuda grass?
The best time to dethatch Bermuda grass is in the spring (March through April), during its peak growing season. This allows the lawn to recover quickly from the stress caused by dethatching and becomes fuller and lusher.
Tips for dethatching your Bermuda grass lawn
- Dethatch your Bermuda lawn only when the thatch thickness exceeds ½”. This is because a thin thatch layer protects the yard from losing moisture and nutrients and protects it from harsh weather conditions.
- Avoid dethatching dormant Bermuda grass, as you may destroy the rhizomes (where the grass stores starch and proteins to survive winter) and kill the lawn.
- Dethatch your Bermuda grass two to four weeks after the spring green-up if you live in an area where it lies dormant during the winter.
- Dethatch your Bermuda grass in March if it doesn’t go dormant during the winter period.
How to know you have a thatch problem
Your lawn may have a thatch problem if:
- The surface feels spongy, puffy, or springy when you touch or step on it.
- The yard looks stressed and has bald spots no matter how well you maintain it.
- The lawn has persistent fungi or pest problems.
The only way you can be sure that you are dealing with a thatch problem is by measuring the thatch thickness. To be sure, dig out a small sample of your lawn at least 3 inches deep using a spade and measure how thick the thatch layer is between the soil and the grass. Consider dethatching your yard if the thatch is more than ½” thick.
How to dethatch your Bermuda grass lawn
Dethatching your lawn means removing the brown layer of dying or dead grass stems to allow water, air, and nutrients to penetrate the soil. If you wish to do the work yourself, here are some steps to guide you:
- You will need to buy or rent a vertical mower or thatching rake from a hardware store near you. Thatching rakes are ideal for small lawns, while vertical mowers work perfectly with larger yards.
- Since you may only need to dethatch once or twice a year, depending on how fast your grass grows, you can just rent the equipment to save on the costs.
- Adjust the equipment’s blades depending on how thick your thatch layer is. You may need to measure the thatch layer to make sure you set your mower to the correct measurement. Be careful not to over-dethatch your lawn, as this can permanently damage it.
- Mow your lawn a bit shorter than usual and water it lightly to make the dethatching process efficient.
- Dethatch your lawn twice, once from the east to west direction and once from the north to south direction, to ensure you cover all the spots.
- Rake up and dispose of the thatch debris, and mow the lawn to get rid of the leftover thatch. If the lawn needs aeration, aerate immediately after dethatching and leave the plugs on the surface as topdressing.
- Water the lawn and reseed it if necessary. After a few weeks, apply a light fertilizer to encourage the germination of the new grass seeds.
Depending on how much it grows, you may need to dethatch your lawn once or twice a year.
Note: Dethatch your Bermuda lawn during its active growing season to give it enough time to recover before the dormancy period.
Do I need to dethatch my Bermuda grass lawn?
The thatch layer is made up of grass stems, roots, and rhizomes that tend to resist decomposition. If left unchecked, the thatch accumulates and starts choking your lawn, preventing water, air, and nutrients from reaching the soil.
It is essential to regularly monitor thatch buildup to ensure your Bermuda lawn is lush, healthy, and green at all times.
Here are the negative effects of thatch buildup:
- Yellowing grass
- Sparse growth and thinning grass
- Constant weed and pest problems
- Inadequate soil moisture and nutrients
- Reduced resistance to harsh weather
The thatch layer may seem harmless at first, but as it accumulates, it can start harming your lawn unnoticed. Typically, new grass starts to root itself on the thatch layer instead of the soil, leaving it vulnerable to pests, pathogens, and harsh weather.
How often should I dethatch Bermuda grass?
This depends on how actively your lawn grows. Bermuda grass exhibits vigorous growth, especially during spring, so you will need to dethatch it regularly to keep it in top shape.
While a thin layer of thatch may be beneficial to your lawn, it should be removed once it reaches a thickness of ½” or more.
For best results, dethatch your lawn once or twice a year, in the spring or early fall. However, do not dethatch a dormant lawn because you may kill it.
How to prevent thatch buildup in your Bermuda lawn
Proper lawn care and maintenance is the only way you can get ahead of your thatch problem. Perform routine maintenance to slow thatch buildup. Here are some tips to guide you.
- Use slow-release fertilizers. Unlike fast-release nitrogen fertilizers, slow-release ones do not cause rapid growth that can cause that buildup.
- Mow your lawn frequently to the recommended height of 1 to 1½ inches and bag the clippings to reduce the amount of organic matter that decomposes on the lawn. This will slow the lawn’s growth and reduce thatch accumulation.
- Water your lawn deeply but less frequently. Deep, infrequent watering encourages roots to grow deep. On the other hand, shallow, frequent watering leads to shallow root growth that can cause thatch problems.
- Aerate your lawn to allow enough water, air, and nutrients to reach the soil. This encourages the roots to grow deeper.
- Increase your lawn’s microbial activity by topdressing or introducing microbes that will break down the thatch layer.
- Do not use too many pesticides on your lawn, as they may eliminate beneficial microorganisms and earthworms that help in thatch breakdown.
Should I scalp my lawn prior to dethatching?
While scalping is not recommended, you may need to scalp your lawn if you have a severe thatch problem. Scalping slows down thatch buildup and makes your next dethatching session more successful.
Scalping entails mowing your Bermuda lawn to a very short height of about ½”. Scalping should be done in early spring before the yard starts to green up. This removes dead regrowth and prevents thatch accumulation. You can use a standard mower set to a low height to scalp your lawn. Once the yard starts to regrow, dethatch it using a vertical mower.
Note: Do not scalp your lawn too low, as you can kill or severely stunt it. Also, make sure you water your lawn well to boost regrowth.
Benefits of dethatching your Bermuda grass lawn
After dethatching your lawn, you will observe notable and positive changes. Here are some of the benefits of dethatching:
- Increased penetration of water, nutrients, and oxygen into the soil.
- Reduced risk of pests and diseases
- Increased resistance to cold, hot, and dry conditions
- Reduced fungal growth
- Improves your lawn’s curb appeal, which can increase your home’s resale value.
FAQ's
Not necessarily. If your lawn has thinning grass or bare spots, overseeding after dethatching is encouraged to improve the lawn’s health and make it fuller and thicker.
You should dethatch your lawn when it is moist but not soaking wet. Dethatching a dry yard will be challenging, and if the ground is too wet, you will pull the turf out by the roots.
The best time to aerate Bermuda grass is late spring to early summer (between April and July). Lawns with clay soil should be aerated twice a year.
This depends on your current lawn problem. If your lawn is failing due to soil compaction, you will need to aerate it. If thatch build-up is the issue, dethatching will work best. Oftentimes, dethatching and aeration go hand in hand.