Our cool season turf grasses love the fall temperatures and extra rainfall autumn brings to Wisconsin. September through October is the best time to apply your last application of turf fertilizer and broadleaf herbicide if needed. The grass is growing more quickly now and needs the extra nitrogen to stay green and healthy as well as store nutrients to get through the cold winter ahead.
Lower your mowing height to 2.5” for the last 2 cuttings of the year. Grass will continue to grow even in cold weather until the ground freezes. Lowering your mowing height will help prevent snow mold and vole damage from occurring during the winter months. A shorter lawn warms up quickly in spring, breaks dormancy and begins to green-up much earlier in spring than longer turf.
Did you know those first annual weeds that you see in spring germinated and grew under the winter snow? Take advantage of the cool weather to do a little extra weeding in your planting beds. Keeping the weeds and their abundant bounty of seeds out of your landscape now will save hours of hard work next spring. A fall application of a pre-emergent herbicide like Preen® is a great way to keep those early weeds in check.
Overgrown and crowded perennials can be divided and replanted until mid-late October. Cut back any perennials that had fungus or mold issues on their leaves this year due to the wet spring weather. Removing and disposing of the infected foliage will help prevent this from spreading next year.
Plant spring blooming bulbs now until the ground freezes. Try mixing several varieties of daffodils together in the same planting group, this will extend your flower show for several weeks. Daffodils are safe from deer browsing and multiply year after year.
Resist the urge to do any extensive shrub or tree pruning in fall; remove only dead or wayward branches as needed to keep the plant looking attractive. Contrary to common belief fall is NOT the time to prune. Pruning will force new growth on plants that will not have sufficient time to harden off before winter. These open wounds and immature growth are more susceptible to winter damage and disease.