ISU Extension and Outreach Horticulturists Offer Fall Lawn Care Tips

September is a great time to aerate lawns in Iowa, according to ISU horticulture experts.
September is a great time to aerate lawns in Iowa, according to ISU horticulture experts.

As the summer winds down, ISU Extension and Outreach horticulturists Richard Jauron and Greg Wallace have recently offered tips for handling and caring for Iowa’s lawns during the fall, including the best times to sow grass seed, fertilize, and aerate property.

When seeding new lawns or overseeding existing lawns, they suggest doing so from mid-August to mid-September for optimal results. The cool nights and warm days of fall present ideal turfgrass growth opportunities and the growing grass will have less competition with weeds. When selecting grass seed, growers are encouraged to go with Kentucky bluegrass for sunny areas and a mixture containing Kentucky bluegrass, perennial ryegrass, and fine-leaf fescues in shaded areas.

When fertilizing a lawn, Jauron and Wallace suggest Iowa land owners do so in late October and early November, when the grass has stopped growing. Those who don’t get to fertilizing in the fall can also see positive results from fertilizing in the spring.

September is the best time to aerate lawns that are growing in heavy, clay soils, as well as those that are exposed to heavy foot traffic. Aerating the lawn relieves soil compaction, prevents thatch accumulation and assists with water and nutrient movement in the soil. Jauron and Wallace recommend the use of core aerators, which have hollow metal tubes. Aeration should be avoided when the soil is dry or wet, as the tubes will not be able to penetrate deep enough (when dry) and may get plugged (when wet).

Land owners that are looking to have more of their questions answered are encouraged to contact the ISU Hortline at 515-294-3108 or