University of Illinois Extension

Fall Landscape Makeover

Fall is the perfect time to get the yard back in shape before cold weather sets in. “Gardeners will see their fall efforts generously rewarded and can look forward to a better-looking garden in the spring,” said Richard Hentschel, U of I Extension horticulture specialist, referring to several lawn and landscaping chores.

“Fall is a great time to refresh the lawn by reseeding smaller patches and sodding larger areas that need quick cover,” he noted. “The typical varieties of grass for full sun areas are bluegrass and actually prefer cooler temperatures to develop.

“Do not wait too long for the first mowing, either. Grass thickens up because we start mowing just as soon as it needs it.”

If you face perennial broadleaf weeds like dandelions, fall is the best time to make treatments, he noted.

“At this time of the year, the broadleaf weeds are moving nutrients into the root system for the fall and any treatments made are more likely to move in that direction, too, controlling the weed at the source,” Hentschel said. “Managing your weeds in the fall means they will not be there next spring.

“If your lawn is in good shape, then a fall fertilizer application using a well-balanced fertilizer is all you may need. Mid-September is about the right time, leaving plenty of time for the grass to absorb the nutrients and still have time to prepare for the upcoming fall temperatures and snow cover.”

Fall is also a great time to increase water penetration and reduce compaction if your lawn is in need of aeration. Core aeration machines are the best type and normally can be rented locally.

“Consider getting your neighbors involved and the cost goes way down,” he added.
Edging flower and shrub beds in the fall accomplishes two things at once.

“Your grass has grown in during the spring and summer, so your beds get back to the right size and, secondly, you will start out next spring ahead of the game with a nice clean edge,” he said. “This takes the early spring pressure away from that task so you can concentrate on other aspects of the landscape.”

Homeowners that have had woody plants die over the summer from insects, disease, and the impacts of the past two summers from drought periods can plant trees and shrubs in the fall. Nurseries and garden centers will have freshly-dug trees and shrubs available in the sizes and flower colors of your choice.

“Some plants are of a more seasonal nature, so be sure to ask which plants do better if planted in the spring,” Hentschel said. “Plan ahead and leave the space open for next spring. Nurseries and garden centers will also have container-grown plants available during this time as well.”

Hentschel said that research is revealing that the recovery time for a plant is directly related to how well the planting hole and the backfill material are prepared.

“Shape the planting hole so that it is much wider at the top than at the bottom,” he recommended. “This allows the portion of the root system that takes up nutrients and water to quickly recover. The backfill material can be amended to increase water-holding capacity and ensure good drainage.”

Roots actually require air in the soil to grow properly. A general rule of thumb for recovery is one year for every inch of trunk diameter.

“If you plant a tree that has a 2.5-inch trunk, it will take at least three years before it fully recovers from being planted in your yard,” he said. “Most trees will also benefit from having the trunk wrapped that first fall, too. Apply the wrap once the weather turns cold and plan on removal by mid-summer.”

Mulching newly-planted trees and shrubs will moderate the soil temperatures by keeping the soil warmer longer, allowing the root system to continue to grow and develop well into the late fall and early fall. Having a mulch layer also will keep the soil colder longer in the spring and avoid the potential rapid soil temperature changes in the spring that can be harmful.

“To be effective, the mulch layer needs to be three-to-four inches deep when it has settled,” he said.

Planting fall mums is a great way to see a lot of fall color in the garden, Hentschel said.

“Get them planted early so they have a chance to develop roots into the surrounding soil so they can survive the fall,” he said. “Plant them as you would any other perennial flower. Gardeners who have planted pansies in the spring will see them again as the cooler weather triggers blooming.”

Gardeners may need to clean up perennials by removing any browning or dead foliage. Removing any spent flower parts will also make those flower beds look a lot better.

“While you are out there, the summer bulbs may be ready to be dug and prepared for fall storage,” he noted. “If you have noticed your spring bulbs are no longer blooming as they should because of overcrowding, late summer is the time to dig and reset those bulbs.”

Watering should continue well into the fall. Plants will look better as a result right up until frost.

“Plants that have enough internal moisture once fall comes will survive much better,” Hentschel said. “New plantings will certainly need that water.”