How to fix patchy grass

When a lawn looks green and lush, it makes the whole yard look great, but if it’s looking far from perfect, you need to know how to fix patchy grass.

Lawns can become patchy for a number of reasons. It might be that it’s not been well cared for in the past and the whole lawn has just become stressed and prone to disease. If a good mowing regimen using the best gas lawn mower or the best electric lawn mower has not been stuck to, it can lead to areas that fail to thrive – but we've got some great tips so you know how to fix patchy grass. 

However, a lack of care is not always the cause for patchy grass and there’s a number of factors that can result in a lawn that looks less than its best.

What causes patchy grass?

As we mentioned, there’s a number of things that can cause patchy grass. However, as David Gower, chairman of the Lawn Association points out, “unless you identify the cause, you may be back to do it again, unless you can alter why it was like that in the first place. And most importantly, when seeding repair patches, choose a grass species to match your existing grass.  Otherwise, that patch may literally be a patch forever…’’

Some causes of patchy grass will be easy to identify and do something about, so they don’t happen again. For example, it might be a high traffic area, or you might have spilled something on the lawn - such as fuel, salt or weedkiller. You may have a dog – dog urine can be hard on grass, so if you can avoid the dog using the grass in this way, this would resolve the problem (of course, this can be easier said than done!).  

Another very common cause of lawn patches is something being left on the lawn. If you have kids it might be a paddling pool, a soccer goal or basketball hoop. A plant or tree that overhangs the lawn can also cause a patch – in this case you may need to cut it back, or accept that grass won’t grow in that area.

Other less easily identifiable problems are pests and diseases - or a ‘dry patch’, which simply repels water.

How to fix patchy grass

So how can you fix patchy grass? David Gower, chairman of the Lawn Association, has a number of solutions, depending on the root case of the problem.

He says, ‘’For spillages, try to identify what it may be that was spilt. Regardless of that, prioritize ‘flushing’ it away from the lawn surface as quickly as you can in order to be able to repair/soil and seed.

"This is the same for dog urination spots. The high ‘ammonia’ nitrogen source within the dog’s urine is too concentrated. Fork the area at very close spacings and using a watering can (you can add dish soap too) soak the area a few times to enable the urine to go deeper away from where you will be putting down new seed.

"For spillages of oil or fuel, digging the area out is a more sensible option. Excavate to about 4-6ins and remove as much of the soil as needed. Then import new soil and add the correct seed.

"If it’s a disease patch, it may need some help, depending on the extent of damage, but nature also has a way of repairing it, with natural growth and grasses covering bare patches.

"If it's dry or hydrophobic soil (often seen in the heat of summer) then the best you can do is to fork the area to 1-2in depth and hydrate it with water mixed with some dish soap. Then soak the area daily. It may not cure, but it will help create a condition that allows new seed to germinate and survive.’’

When it comes to filling your patch there are two options - seed or sod. Sowing seed is easy and inexpensive. But you need some patience, as it can take as long as six months for the patch to become completely blended into your original lawn. You also can’t mow the patch for a good few weeks.  

You could also choose to repair the spot by cutting a piece out of a roll of grass sod. If you have a few areas to sort out, this might be the better option.

Whichever method you choose, try to time the job for the start of the growing season in spring, so that the grass has had time to establish itself before winter. It’s worth asking for advice from your local garden centre so you get the right grass at the right time for your growing region.

To prepare the ground for seeding, use a form to dig down a couple of inches and break up the soil, removing any weeds or stones. Mix in some compost or good-quality top soil, to give your seeds a decent start. Rake it through together and then tamp it down, so the ‘patch’ is level with the rest of the lawn. 

Sow seed in a thin layer (you could instead choose to use a patch repair product, as this will include not only seed but also mulch and fertilizer). Cover with mulch and then water. You can fertilize once the new grass is established. Don’t be tempted to mow until it has grown higher than your existing lawn!

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