Wild Fall Garden

By Lori Rotenberk

How to leverage the transitional beauty of autumn

It’s not uncommon to experience a pang of sadness when summer’s light begins to shift toward autumn — especially when looking out over your garden. Many of the vibrant flowers have lost their summer blooms. Stems and leaves have begun to fade.

But the arrival of fall need not mean the decline and fall of your garden. We asked a handful of Chicago-region botany and design experts to share their ideas on preparing a native garden for fall (and, in turn, preparing a fall garden). It’s a period of opportunity, for new colors and deepening texture. Without much fuss, gardeners can leverage autumn’s natural tendencies and emphasize the transitional beauty of this exciting season.

Flower Power

Don’t write off flowers prematurely — just because kids are in school doesn’t mean the growing season is over. With the right native species, bright flowers can continue through late October.

Some fall superstars include the whites, pinks, blues, and purples of the asters. Keith Nowakowski, a landscape architect and author of Native Plants in the Home Landscape for the Upper Midwest, favors New England and sky blue aster.

Silphiums, including prairie dock, compass plant, and cup plant, as well as several native goldenrods, will add bright yellows. Bottle gentian contributes bulbs of bright royal blue. If you want to enjoy new adult plants this fall, landscapers recommend adding them before daytime temperatures drop below 60ºF. (See sidebar for more ideas.)

Multifaceted Fall

Flowers get most of the attention, but changing leaves, fruit, and even bark are often overlooked as ways to bring color and texture to a garden. The changing leaves of a native garden can be just as impactful as its flowers. Sumacs provide a gorgeous palette of oranges, yellows, and reds. And chokeberry leaves offer a dash of bright red.

Several shrubs, trees, and forbs bear fruit in the fall that often lasts throughout winter. Consider winterberry, sumac, Solomon’s seal, or even black chokeberry. The berries of maple-leaved viburnum will dot a garden with red, black, and purple. Nowakowski likes planting pasture rose with his asters, since in fall it bears a red fruit and has bright orange-and-yellow leaves. Red osier dogwood will add height as well as color; the shrub’s fine, deep red stems go well with grasses and arborvitae.

Finally, don’t rule out green for fall. Nowakowski recommends Christmas or woodshield fern and trailing junipers.

Autumn Cleaning

A minor cleanup will tidy your garden and help bring needed light to the soil in spring. But the less ambitious the cleaning, the more natural your garden will look, says Connor Shaw, a purveyor of native plants and owner of Possibility Place in Monee, Illinois.

One of the first things Shaw suggests be done is absolutely nothing. “Let things lay,” Shaw urges. “As the plants begin to die back, you can cut back — it won’t hurt the plant, and I’ve never heard one scream. But the best way to make it look good is to not prune, so you have interesting shapes.”

For gardens where controlled burning is an option, fall is a good time of year to reset the ground to a flat, black slate — but only if you’re ready to limit the beauty of your garden for the season, says Heidi Natura, owner of natural landscaper Living Habitats.

Prep For Next Year

Gardeners can also use autumn as a time to prepare for spring. Be certain to incorporate all organic matter back into the site. Mulch with fallen leaves, wood chips, or pine boughs, as it keeps the ground warm, protects plants, and adds nutrients to the soil. Let tree leaves lie where they fall. If you rake your lawn, put some leaves into the garden.

Pat Armstrong, a Naperville-based ecologist and botanist who owns Prairie Sun Consultants, finds fall to be a perfect time to harvest and scatter seeds. “If you have trees or shrubs with berries, squish them into the ground, and you will plant more where you want them to grow,” she says. You can often tell when seed heads are ripe when they easily come off the plant into your hand. Scatter them where you like, and gently rake them into the soil.

Fall is a good time to divide and transplant existing plants. This is also the season to get spring wildflower bulbs into the ground for next year. Move plants, especially spring wildflowers, now, while they are dormant. Since they may be entirely underground at this time of year, it may be helpful to mark them with a stake when they’re still visible in the spring or summer. Dig them up with the entire plot of soil they’re growing in.

Anticipate Winter

Many designers are drawn to native plants because of the way they weather the winter. If you already have grasses in your garden, you know they add grace and volume in both fall and winter. Their thin leaves often hold color and their form remains interesting when they die back. “Their golden hues can be a background canvas” against which the elements and other plants work, says Armstrong. She revels in the way grasses hold ice and snow. “Others look pretty when wet,” she says. Her favorite is switchgrass. Nowakowski suggests little bluestem. “The blue-green foliage in the summer and copper color in the fall goes with everything,” he says.

Wildflowers with large, architecturally splendid seed heads, such as yellow and pale purple coneflowers, rattlesnake master, and blazing star provide continued points of interest, standing tall and distinct above most snowfalls. Shaw is partial to Annabelle hydrangeas. “When it snows,” he says, “they look like ice cream cones.” Wild bergamot reminds Armstrong of crystallized candelabra. Native sunflowers, says Natura, add massive height and drama.

As plants finally fall back to the earth, built elements — fences, trellises, and sculptures — take on more prominence, and can continue to provide structure, order, and interest, especially past December.

Once you have your garden in shape, sit back and enjoy. Fall and winter light can dazzle. Overcast days make the greens all the greener, and sunny days make the golds shine. Although it may seem that you may never see spring shoots, think of what lies dormant below the ground. The bulbs and tubers have stored their nutrients. Roots are protected. All that remains is to appreciate the garden in all of its wild beauty.

Related Article:

Unlock Your Yard! Getting Started with Native Plant Gardening, CW Spring 2002

Native Garden Oasis, CW Spring 2004