How can it be that the leaves are turning, combines are rolling and Halloween is just around the corner, yet I am writing about lawn care? When it comes to lawn care, fall is an important time of year. What you do now can have a significant impact on the health and appearance of your lawn next year. Be sure to pay special attention to the following management tips.
Mowing. It is important to continue to mow your lawn until it stops growing, which will typically be November (a long mowing season provides the added benefit of more exercise opportunity). Kentucky bluegrass should be mowed to a height of two and a half to three inches. Never remove more than one third of the leaf surface at a time. For example, if you normally mow to a height of three inches then cut the lawn when it reaches four and one half inches.
Fertilization. Best results occur when you fertilize once in the spring and twice in the fall. Fall applications can be made in September and early November. Fertilizing in September helps to thicken the turf and promote shoot growth. The November application promotes root growth and early green up in the spring. Apply one pound of actual nitrogen per one thousand square feet in each fall application.
Weed Control. Dandelion and other perennial weeds can be controlled with the application of broadleaf herbicides from mid-September to early November. Most broadleaf herbicide products contain a mixture of the following chemicals: 2,4-D, MCPP and dicamba. Fall applications of broadleaf herbicides are more effective and safer than those made in spring or summer. The risk of herbicide injury to vegetable and flower gardens, fruits and ornamentals is less. In preparation for winter, perennial weeds move food down to their roots in the fall. Broadleaf herbicides will also move to the weed's roots, resulting in excellent weed control. Before applying any pesticide, carefully read and follow label directions.
Aerification. Consider aerification if compaction is a problem in your lawn. Aerification relieves soil compaction, improves air and water movement into the soil and helps reduce thatch accumulation. Aerify lawns in September with a machine that has hollow metal tubes or tines. These tubes or tines remove plugs of soil from the ground. Avoid spike-type devices that simply punch holes in the turf. For maximum benefit, the core aerifies should penetrate the soil to a depth of two to three inches. When finished, there should be approximately twenty to forty holes per square foot. After aerifaction, break up the soil cores by mowing or raking.
Raking. Rake leaves and properly dispose of them. Small amounts of leaves can be shredded with the lawnmower and left on the lawn. A thick cover of leaves on the grass can damage turf. You may want to consider composting your leaves. To learn more about composting, consult publication PM 683, Composting Yard Waste, which is available through the extension office.
For more information, contact the Grundy office of ISU Extension at 319-824-6979.