Brown patches and bare spots are one of the great annoyances in lawn care. Not only do they look bad, they are an invitation for weeds to set up shop in your lawn. Fortunately, with a little effort on your part, these trouble spots can be fixed. Even better, you can take steps to make sure they don't return.
Before you can fix the problem, you need to determine what caused it in the first place. Here are some of the common causes of patchy lawns and how to deal with them.
Too Much Fertilizer
That's right, too much fertilizer in one spot can actually burn the grass and result in big brown patches. The cure? Well, there really isn't a fast fix for this problem. The good news is that excess nitrogen (the typical cause of fertilizer burn) leaches out of the soil fairly quickly, so start by watering the brown spot thoroughly. After about a month, try putting out new grass seed.
In the long term, you may be better off using a liquid or organic fertilizer. You can also try cutting back on fertilizer and adding nitrogen in other ways, like leaving grass clippings on the lawn to decompose.
Has the neighbor's dog been, err, "visiting" your lawn? The resulting patches are actually caused by the same problem as fertilizer burn - too much nitrogen. The short-term cure is also the same: water the spot thoroughly to leach out the nitrogen, and then re-seed. If you really soak the lawn right after the dog is done, you may be able to prevent the grass from burning in the first place.
To keep this problem from happening again, you should have a word with the dog's owner. If the visits persist or you can't identify the guilty party, a good strong fence may be the best way to go.
If your brown patches look more like brown paths, then maybe friends, family and visitors have been taking short-cuts through your lawn! This can cause problems even if the traffic occurs in the middle of winter, because the soil compacts from all that walking and then water can't get to the grass roots.
You can fix this problem by aerating the soil. If the area is very small, just stick a garden fork into the soil several times to loosen up the thatch and ground.
Another solution is to have your entire lawn professionally aerated once or twice a year.
Over the long term, the best way to prevent traffic on your lawn is to lay out clear pathways, so that visitors can see where to walk. There's the added benefit that a well-laid pathway will add beauty and value to your lawn.
Too Much Water
If you get a little over-enthusiastic about watering your lawn, you can end up killing your grass with kindness. Too much water will drown the roots and rot them, causing dead spots in the grass.
To fix a dead patch caused by overwatering, first try to figure out why there's too much water in that spot. Does the lawn slope down and naturally drain to that area? Is something preventing the water from draining away? Perhaps installing a drainage pipe is the way to go. Once the spot has dried out, re-seed and keep an eye on the area to be sure it's no longer turning into a bog.
The lawn disease known as "Brown Patch" is caused by a common fungus. This fungus can exist in the soil without any symptoms for years, since the grass will not react until it becomes stressed from one cause or another. When Brown Patch does appear, it takes the form of small brown spots that rapidly enlarge in warm weather. The patch will be shaped like a ring surrounding healthy green grass.
The only way to confirm that your problem is caused by Brown Patch is to have the grass tested. Most county Extension offices can help you with this. Once your diagnosis is confirmed, apply a fungicide to the affected area and the problem should clear up.
You can never completely eliminate the fungus that causes Brown Patch, as it lives deep in the soil. When the grass has recovered, the best way to keep the patches from returning is to keep your grass from becoming stressed again. Proper application of fertilizer and regular watering will keep your lawn healthy and happy.