Red Patch disease - Ask Extension
Hello, I believe much of my lawn has Red Patch disease. Could you please confirm, I have attached 2 pictures. I have recently read that applying ni...
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Red Patch disease #869169
Asked May 19, 2024, 9:04 PM EDT
Hello, I believe much of my lawn has Red Patch disease. Could you please confirm, I have attached 2 pictures. I have recently read that applying nitrogen may help. This spring I applied Halts pre-emergent but just the pre-emergent, not the kind that has turf builder in ii so no fertilizer has been applied, I usually only apply a fall fertizer. Do you recommend applying Nitrogen to the lawn and if so, how much? Thank you.
Howard County Maryland
Expert Response
We can't confirm a diagnosis from the pictures, but Red Thread has been abundant so far this spring in many home lawns, and the symptoms can overlap with those you photographed. (Similar-looking diseases, like Pink Patch, can also occur now, and even early stages of Brown Patch appear to be starting in some areas.) Rarely is a fungicide warranted, nor can one cure any existing symptoms.
For Red Thread, usually the best approach is to apply a modest dose of nitrogen fertilizer to force the turf to outgrow the damage, as you noted. Applying too much nitrogen (like a "normal" dose) will increase the risk of contracting Brown Patch later. Using a phosphorus-free fertilizer (unless a soil test has indicated a phosphorus deficiency) at a rate about half of the application dosage of what the bag recommends, should suffice to provide the right amount of nitrogen. (Aim for approximately a half-pound of nitrogen per thousand square feet.)
Miri
For Red Thread, usually the best approach is to apply a modest dose of nitrogen fertilizer to force the turf to outgrow the damage, as you noted. Applying too much nitrogen (like a "normal" dose) will increase the risk of contracting Brown Patch later. Using a phosphorus-free fertilizer (unless a soil test has indicated a phosphorus deficiency) at a rate about half of the application dosage of what the bag recommends, should suffice to provide the right amount of nitrogen. (Aim for approximately a half-pound of nitrogen per thousand square feet.)
Miri
