The Washington State University Extension recommends fertilizing perennial rye grass and other grasses with nitrogen in late spring, mid-June, early September and late fall, after the last mowing and before the soil freezes. Sulfur should be applied twice a year, in early spring and late fall.
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Aileen Clarkson has been an award-winning editor and reporter for more than 20 years, earning three awards from the Society of Professional Journalists. She has worked for several newspapers, including "The Washington Post" and "The Charlotte Observer." Clarkson earned a Bachelor of Arts in journalism from the University of Florida.