Seed heads give perennials another season of interest

There are at least three good reasons to leave seed heads standing in the garden instead of cutting them back.

First, they provide food for birds in the fall and winter. Next, they offer interest to an otherwise lackluster winter landscape. And finally, they may give the gift of new plants to gardeners.

Finches and other songbirds perch on large seed heads while they devour the seeds of coneflowers, false sunflowers, black-eyed Susan and gayfeather. Their color, exploits and songs of gratitude are the reward to gardeners for helping them survive northern Illinois winters.

Plant gayfeather in mass and appreciate their strong vertical lines in the winter landscape. The seed heads of coneflowers and black-eyed Susan are showcased when planted in front of the tawny foliage of ornamental grasses, such as maiden grass or switch grass. False sunflowers belong toward the back of the border where their seed heads stand guard over the garden.

Some seed heads are almost as pretty as the flowers that bloom before them. Consider planting some of these perennials with noteworthy seed heads when choosing new plants for your beds and borders:

The flattened, plate-like seed heads of yarrow are a striking contrast to the shapes of many other seed heads. Coronation Gold, Moonshine and Saucy Seduction all have stiff stems that hold their seed heads proudly through all but the heaviest snows.

Coronation Gold tops out at 3 feet tall; Moonshine is a bit shorter. Both sport sunny yellow blooms. Saucy Seduction boasts intense fuchsia flowers on plants topping out at 18 to 24 inches tall. Yarrows grow best in a sunny spot with well-drained soil.

Ornamental onions feature small, globe-shaped seed heads that hold their shape through winter. Millenium is truly a four-season perennial. Flattened strappy foliage is quick to emerge in spring; Bright rosy-purple flowers begin blooming in midsummer and continue into fall; and seed heads provide winter appeal. Alliums should be planted in full sun or light shade.

Astilbes allow shade gardeners the opportunity to enjoy spectacular seed heads, too. A drift of astilbes is an eye-catching display of feathery plumes in summer and dried seed heads in fall and winter. Amber Moon shows off chartreuse foliage and spikes of rosy pink flowers. Visions flaunts raspberry-purple blooms over glossy, green foliage. Plant astilbes in moist soil in part shade.

Joe-Pye weed is one of my favorite perennials. Foliage held on sturdy wine red stems rise from the soil in spring; mauve pink flowers bloom from midsummer to fall; and flat-topped seed heads hold light snow like frosting on a cake. Gateway reaches up to 5 feet tall. Little Joe grows 3 to 4 feet tall and Baby Joe tops out between 2 and 3 feet. A butterfly magnet, Joe-Pye weed belongs in every sunny garden with moist soil.

The strong stems of sedum hold long-lasting flower clusters from late summer into fall over succulent foliage. In winter, snow embellishes their seed heads. Carl is an upright cultivar topped with bright pink flowers. Purple Emperor displays deep purple foliage and rosy pink blooms. The most commonly-grown sedum variety, Autumn Joy, sports dusty pink flowers that deepen to reddish bronze.

Some perennials self-seed, giving gardeners the gift of free plants. Don't deadhead short-lived perennials like blanket flower and mallow, and spare the seed heads of biennials like angelica and hollyhocks. Their seed heads will drop seeds that grow into their own replacements.

• Diana Stoll is a horticulturist, garden writer and the garden center manager at The Planter's Palette in Winfield. She blogs at gardenwithdiana.com.