Lawn moss and red thread in a lawn

Asked February 14, 2019, 3:09 PM EST

I just treated my lawn for moss today(2-14)Can I treat for red thread as well or should I wait for a period of time AND can u recommend the best fertilizer for red thread and is it ok to do it now or wait til later in the spring. Please advise, I'm gettiing so many different opinions. Thank you so much, Ron

Lane County Oregon lawns and turf

1 Response

Hello,

What did you apply for moss? If you applied a moss control fertilizer then you probably do not need to apply more fertilizer for the red thread unless the fertilizer you used did not have nitrogen in it, was a slow release source of nitrogen, or you did not apply a high enough rate of nitrogen. If you nitrogen rate was high enough and not a slow release source, you should see a growth response and a green up in about 2 weeks.

Red thread is a fungus that is much worse under low fertility (i.e. low nitrogen) and is particularly bad on perennial ryegrass lawns or perennial ryegrass and red or chewings fescue lawns. You can reduce red thread by applying fertilizer in the fall. Most fertilizers will work then because soil temps are still warm. In February, however, soil temps are cold, so you need to apply a soluble quick release fertilizer like ammonium sulfate or urea. You need to apply 1 lb of nitrogen per 1,000 sq ft. Therefore, if you are applying ammonium sulfate 21 - 0 - 0, you need to apply 4.76 lbs of ammonium sulfate to 1,000 sq ft to get 1 lb of nitrogen (1 lb of nitrogen divided by 0.21 (nitrogen percent/100) = 4.76 lbs of ammonium sulfate fertilizer). If you use urea, you only need to apply 2.17 lbs per 1,000 sq ft (1 lb of nitrogen divided by 0.46 (nitrogen percent/100) = 2.17 lbs of urea fertilizer.

Good luck.