Marianne's Response

Removing thick thatch

We have dead spots in our lawn with matted down grass that develops thick thatch. Many lawns in surrounding neighborhood have this problem. We are located around Farrelly and Edith Ave but problem is widespread. Some people have lawn service. I don’t but thatch and aerate and fertilize regularly. Neighbors are asking me what to do. I used to keep up by removing spots and replanting. This year it has taken over like so many lawns in the area. Is there any help? It is very visible in most lawns behind Sacred Heart church. I live at 3015 Edith Ave. Please help. Want to start reseeding soon. Sorry, could not send small enough picture. It is such a widespread problem we were hoping you could visit the area and see for yourself and then post a response in your Herald column. Thank you. We all hope to start our spring lawn care soon or start over with new lawns.

Posted by Duane Simurdak on March 5, 2015

Marianne's Response

Thank you for giving me a physical location to check this out. It sounds like you may have red thread and fungal infection common in cool areas. Believe it or not lawns that get a lot of high nitrogen fertilizer suffer the most - too much fast, soft, weak growth. Do not overfeed your lawn. There other problem is a lawn weed that is a grass called poa annual - if you live near pastures it will escape from pasture land and reseed in your lawn. My advise is to aerate, add lime, topdress with sandy loam and reseed right on top of the old lawn. Now mow high - set the mower to 2.5 to 3 inches. A taller lawn will shade out the invasive grasses. Your tall lawn will still look nice if it is level - so fill in those low spots and dips. Just say no to the low mow and you'll have a lot less problems in cool and rainy Western Washington. Keep growing, Marianne Binetti

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