Will County gardeners can flip the calendar to fall yard care

It was definitely still summer this past week with heat indexes surpassing 100 degrees, but the home garden calendar says it is time to look to fall.

Spring may be the most anticipated season for area garden enthusiasts, but what happens in autumn can make all the difference in terms of trees, shrubs, perennials and grass.

“There is so much focus on gardening in the spring,” said Nancy Kuhajda, University of Illinois Extension Will and Grundy master gardener coordinator.

“However, what homeowners do at the end of the growing season often determines how good your next year is going to be,” she said.

With a mission of helping others learn to grow, the University of Illinois Extension Will and Grundy Master Gardeners has more than 100 volunteers who answer gardening questions over the phone, via email or even in person.

Kuhajda said sometimes the Extension gets calls from area homeowners wondering why their early spring bloomers such as lilacs, forsythia and spirea have no flowers.

Kuhajda first asks if they pruned the plants in the fall.

This, she said, often explains where the flowers went.

Kuhajda stressed homeowners should not prune trees or shrubs in the fall.

“Plants are getting ready to shut down and sometimes pruning can stimulate the plant to grow,” she said, “combined with late, hot falls, the plants will put on new stems which will be winter killed.”

In addition, Kuhajda recommends not fertilizing perennials, trees or shrubs after July 1.

Fertilizer is a stimulus to grow – and not a medicine, she said.

“Applying fertilizer to plants, even at the wrong time of year, the plant will grow,” Kuhajda said.

Woody plants need two parts of the year – a growing part, which occurs from April to July, and another critical time is July until the end of the year.

The plant is hardening the wood so it can make it through winter, Kuhajda said.

“By encouraging woody plants to grow in the fall, the new wood will be winter killed because it didn’t have that second phase,” she said. “It is wasting the energy of the plant.”

In terms of annual plants which only live one growing season, Kuhajda said to continue to water and fertilize them throughout the next weeks.

“In summer or early fall, cut them back significantly if they have become straggling. That will stimulate them to grow additional flowers – which are critical for the monarch butterfly,” she said.

The monarchs that hatch now will be taking a nine-month, 4,000-mile migration to Mexico. “They need all the energy they can get,” she said.

Lawn care

Grass mowing should continue throughout fall, according to Kuhajda.

If left too long over winter, homeowners will be left with snow mold patches of grass.

Lawns are typically fertilized four times a year, Kuhajda said.

“For those who want to minimize the amount of fertilizer they put on their lawn, if you only do one, the fall treatment is the one to do,” she said.

Every season, Kuhajda recommends assessing lawns to determine if weeds or bare spots are a bigger problem.

Homeowners can only address one a season, she said.

“People make the mistake of applying their weed and feed and then put down grass seed,” Kuhajda said.

“The weed killer is going to prevent the grass seed from growing,” she said. “It recognizes it as something that should not grow.”

If bare spots are more of a concern, Kuhajda recommends seeding between mid-August and Sept. 15.

“Starting now, the grass will have seven weeks to grow,” she said.

Seeding in the spring can fail, if the weather gets too hot too fast, Kuhajda said.

Fall blooms

Chrysanthemums, the traditional fall flower, are beginning to appear at every garden center, Kuhajda said.

“They are considered hardy mums – meaning they are perennials,” she said.

Sometimes, people don’t have success with them coming back year after year.

When transplanting mums to the ground, Kuhajda suggests cutting the mum back by half and putting them into ground after they are done blooming.

“Loosen the roots and water until the ground freezes,” she said.

Fall also is an excellent time to transplant perennials.

Ideally, she said, it is best to dig the entire plant out and use a sharp tool such as spade or knife to cut the plant sections.

The most important step is to replant the plant at the same depth it had been planted before, Kuhajda said.

Leaf pickup

While tree and shrub leaves often end up in a lawn bag at the end of a driveway, they also can be used to enrich gardens.

Mowing the leaves into smaller pieces and putting them in a pile will allow them to decompose and by spring, homeowners will have their own homegrown organic compost, Kuhajda said.

“It is letting nature take its course, just like on the forest floor. Leaves really translate into gardeners’ gold,” she said.

For gardening questions for the University of Illinois Extension Serving Grundy, Kankakee and Will Counties, call 815-727-9296 or email questions to kuhajda@illinois.edu.