Proper fall care helps ensure healthy lawn next spring
By Justin Moss, directo, UW Sheridan Research and Extension Center
Proper fall lawn care for cool-season grasses such as bluegrass, fine fescue and turf-type tall fescue is important to ensure a healthy lawn next spring.
The last mowing will usually occur sometime in September or early October. The mowing height should be between 2 to 3 inches, and be sure the blades are sharp.
If possible, mow frequently with a mulching blade, and let the clippings stay in the yard instead of bagging. Try not to remove more than one-third of the leaf material during each mowing.
Thatch is a tightly intermingled layer of dead and decaying plant material just above the soil surface. The primary component of a thatch layer is turf grass stems and roots. Short grass clippings, dropped on the lawn after mowing, are not the cause of thatch buildup because they break down rapidly in a regularly mowed yard.
Thatch layers are typically the result of bad cultural practices such as over fertilization and over watering. In Wyoming, grass generally needs about 3 to 5 pounds of nitrogen (N) per 1,000 square feet of turf per year. N is typically the limiting essential plant nutrient in Wyoming soils, while phosphorous (P) and potassium (K) levels vary; therefore, soil testing (see information below) is strongly recommended to detect problems or deficiencies before money is invested in fertilizer.
If the thatch layer is thicker than one-half to three-quarters of an inch, it can restrict the movement of air, water, fertilizer and other materials to the roots. Power raking next spring can help reduce the thatch layer if needed. A power rake can be rented for larger yards, or small yards can be hand raked.
For more severe thatch layers and/or compacted soil, core aeration may be needed. A machine can also be rented for this procedure, or a lawn maintenance company can be hired.
Fall fertilization of bluegrass and turf-type tall fescue should occur in early to mid-September, normally at the rate of 1 pound of N per 1,000 square feet using a slow-release, complete fertilizer such as 25-5-5. This particular fertilizer would have 25 percent N and 5 percent each of P and K.
To figure out the amount of fertilizer needed in terms of N, divide 100 by 25; therefore, 4 pounds of fertilizer would be needed to cover a 1,000 square foot lawn.
The rate for fine fescue is normally one-half to one pound of N per 1,000 square feet. Be sure to use properly calibrated equipment. To help make things easier, use a name-brand fertilizer with a matching name-brand spreader.
An additional fertilization at the same rate can occur in early October to early November if the bluegrass or turf-type tall fescue is still green. A second fall fertilization of fine fescue is not required.
Fall fertilizer applications are not required for the two popular warm-season grasses in Wyoming – buffalograss and blue grama.
Annual fertilization schedules are contained in the University of Wyoming Cooperative Extension Service (UW CES) bulletin Landscaping: Turf in Wyoming. Information is listed below.
The UW College of Agriculture provides soil testing services.
Soil testing information sheets can be obtained at any UW CES county office in Wyoming (contact information is at http://ces.uwyo.edu/Counties.asp). They also are available online at www.uwyo.edu/renewableresources/soil/soil_lab.htm.
There is a $20 fee for the standard test, which includes pH, salts, organic matter, phosphate-phosphorus, nitrate-nitrogen, lime and texture. There is a $4 fee for additional tests. The lab can be reached at (307) 766-2135.
Irrigate lawns as needed in the fall. Try to water deeply and infrequently in the early morning. Do not irrigate so much at one time that water runs off the surface.
Autumn is also a good time to think about weed control. Pre-emergent herbicides can be applied in the fall or late winter/early spring. Choose a product labeled for your type of grass. Always read the label when applying pesticides, and use properly calibrated equipment.
The best defense against a turf disease is to have a healthy lawn. Chemical control can be useful if needed, but proper cultural practices greatly reduce the need for chemicals.
If you think you have a turf grass disease, contact a local UW CES office for identification.
A number of lawn and garden bulletins are available on the UW CES Web page at http://ces.uwyo.edu/PUBS/Horticulture/Horticulture_Publications_Main.htm.
Among them are:
Keep Ahead of Lawn Drought, B-682R.
Low-Maintenance Grasses for Revegetating Disturbed Areas and Lawns, B-1070.
Landscaping: Turf in Wyoming, B-1129.
Bulletins are also available from local CES offices or by e-mailing cespubs@uwyo.edu.Contact: Robert Waggener, Editor
Phone: (307) 766-3571
E-mail: robertw@uwyo.edu###
Back to CES Home page