Mark McCauley, Resource Conservationist
As Fall has arrived our minds might be turning to things we need to do around the home to prepare for winter, but that may not necessarily include our lawns. People are prone to think that the grass has done its thing all year, and now will be going into a dormant period and not really need much attention until next growing season …Spring. However, does it really stop growing completely during the colder months? In reality, cool season grasses (which account for most lawn mixes locally) do continue to grow underground, even during the winter, although much more slowly. Providing your lawn the right fertilizers it needs in the Fall will help it create and store the necessary reserves (carbohydrates) to keep building a healthy root system, one of the keys to a beautiful resilient lawn next Spring. Penn State Extension explains it this way; “Lawn fertilizers are often marketed as 'plant food'. Although most people realize that nutrients from fertilizers are required by plants for proper growth and development, they may not realize that fertilizers are not really plant food. Plants make their own food through photosynthesis, a chemical reaction in leaves involving water, carbon dioxide (CO2 ) and light energy. The end products, carbohydrates, are used by plants for energy and growth and are the true plant food” (source). Fall fertilization may be far from the minds of many homeowners, but it shouldn’t be. Taking the time to perform some simple fertilizer applications this Fall will likely pay off big next Spring ! Completing a soil test to determine nutrient needs is also a good idea. You don't want to overfertilize as that can lead to water quality issues in storm water runoff. Information about soil testing can be found on our website at: https://www.hamiltonswcd.org/soil-testing.html
Fall Weed Control
But what about broadleaf weed control? Could that also be an issue to address in the Fall? Aren’t weeds also going into the winter and entering a dormant period? Well, not actually for several problem weeds. Some, like Chickweed, germinate as tiny plants under the grass canopy in the Fall, and will be there ready to take off growing in full force next Spring. In that regard, Fall weed control can be a very effective management tool in controlling problematic broadleaves. Applying the right herbicides going into the fall can outright kill the weed, or at least weaken it going into the winter, when it will die from lack of reserves. Kansas State Extension discusses the issue of fall weed control: “Broadleaf weeds such as dandelions, henbit and chickweed all germinate in the cool, moist periods of September and October. They overwinter as small plants no larger than a quarter. Arrival of warm spring weather promotes the weeds’ rapid growth and flowering. Once plants reach the flowering stage, they are practically impossible to control. The advantage of fall control is that the seedlings are not well-established. This is the stage at which control methods are most effective”(Source).
Good Resources Available Through Purdue University
See links below for excellent publications to help you manage your lawn.
Taking Care of Your Yard, The Homeowner's Essential Guide to Lawns, Trees, Shrubs, and Garden Flowers H0-236-W
Lawn Improvement Programs AY-13-W
Maintenance Calendar for Indiana Lawns AY-27
Control of Broadleaf Weeds in Home Lawns AY-9-W