What are Those Brown Patches in a Lawn?
In April, discussions of extreme drought and the need for water were rampant; especially talk about stressed areas of turf that were browning rapidly.
Fortunately, heavy rains came, put an end to the drought, and most lawns recovered nicely.
So, what are these new brown patches on some lawns?
The answer is Red Thread and Pink Patch.
These diseases occur during cool, wet weather and heavy dews, all of which there has been plenty of over the last month. As fungicides are typically not needed to cure these lawn ailments, fertilization will help "flush out" out the brown spots and a lawn will recover.
It is also important to be mindful of the duration of watering, the longer the better. Too much short duration watering may promote more disease. From now, through summer, a lawn should receive two to three deep soakings per week, but be careful not to over water during high humidity, daytime and early evening.
Often, the home owner will water when any sign of browning is present in the lawn. It is important to differentiate between drought stress (needing water) and disease (hold back on watering). For drought stress, dig into the soil and one will notice very dry soil. For disease stress, the blade of the grass will show signs of disease. Close observation of the blade will show a pink-colored cotton for pink patch, and a reddish thread for red thread.
There are many other diseases to watch for during the summer months that can be injurious to a lawn such as brown patch, leaf spot, dollar spot and pythium. Research these diseases on the Internet and learn about them before deciding water is the best solution every time one sees browning in a lawn.
Other tips for reducing disease include:
- Maintain soil pH between 6.0 and 6.8.
- Maintain balanced fertility of NPK.
- Keep mower blades sharp to minimize leaf wounds.
- Aerate a lawn if thatch layer is 1/2” or more.
- Pickup grass clippings during mowing when disease is present.
Paul Lauenstein
1:52 pm on Monday, June 11, 2012
I never water my lawn, and it looks great most of the year. Sure, it goes dormant in especially dry summers, but it always comes back in the fall. An application of weak organic fertilizer mixed with lime in early spring and early fall, mowing tall (3") with a sharp blade, and leaving the clippings on the lawn to feed the night crawlers that aerate and fertilize the soil are all it takes. I save a lot of money by not irrigating at all, plus I help Sharon's water quality and spare water for our local environment. I have not had any outbreaks of red thread or pink patch. Healthy soil, rich in organic content which holds moisture, is key. That's why I use organic fertilizer and leave the clippings on the lawn, which decompose and enrich the soil over the years.
Kurt Buermann
6:29 pm on Monday, June 11, 2012
We keep our grass area to a minimum by having islands of ground cover, pachysandra or myrtle. Within these we plant flowers. We also have several (easy to create ) ponds. Further we maintain a 15 to 30 foot border of natural forest surrounding our (1 acre) property. This gives a nice sense of privacy as well as being a convenient and environmentally sound place to put fall leaves. We, like Paul above, let grass clippings either remain on the lawn or use them for mulch in the garden. We fertilize once a year --if that-- with an organic fertilizer if we think the lawn needs it. We cut the grass to about 3 inches. In the fall we rake sparingly, then just run over the remaining leaves with the lawn mower, and letting the small pieces remain on the lawn.
We hardly ever (I can't remember the last time.) water the lawn. Sometimes we water flower or garden beds for half an hour or so with a hand held hose, doing so in early morning or evenings so the water will not evaporate in the heat of the day.
Some new lawns are planted over a sandy soil (created during home construction and lot land scraping). Having removed the natural topsoil, the developer then trucks in a thin layer of store-bought topsoil. Admittedly, these lawns might need more watering in their infancy. However, gradually improving the lawn (grass clippings, leaf bits in fall, and limestone do wonders) in a few years the lawn should certainly not need three deep soakings a week, let alone per year.