IN THE GARDEN for May 2013

Rachel Anderson, Nebraska Statewide Arboretum

            For a healthy landscape, it is often a good idea to imitate nature. In the natural world, a plant does not exist in a vacuum. It grows as part of a population that shifts and renews itself in a never-ending search for ecological balance. Luckily for the gardener, interweaving different plants together makes for some stunning combinations.  

In the garden, prairie plants especially benefit from companions. When planted alone, these beauties can get floppy. This is because many of them evolved with so much competition that they did not need the “stay upright” gene, so to speak. These plants rely on each other to hold them up, so bringing this principle into the garden comes in handy. There is no need to fear goldenrod or pitcher sage when they are intermixed with a “prop” plant like switchgrass. Additionally, some plants (like beardtongue and larkspur), may not have the substance to hold their own visually year-round and are more attractive among grasses and other plants. 

When selecting plants to use together, the ideal combination is one in which the plants make each other look better all year long. This may seem hard to do, since many plants make a fantastic pairing in bloom or in autumn but might look disheveled the rest of the year. The secret cure-all solution to this issue is simple: put a grass in there. Grasses (and grass-like plants) provide the texture and structure necessary to polish off any combo. And if the area in question is shaded, no problem—many types of sedge thrive in part shade, and grassy plants like fern and liriope would work well, too. 

            Try out these pairings for landscape combinations that span the seasons. And remember that letting these plants reseed is a good thing, not only because it will eliminate bare spots and choke out weeds, but because a self-perpetuating population is much more sustainable in the long run and serves as prime habitat for wildlife. 

            For sunny areas with dry to average soil:

  • Butterfly milkweed, sideoats grama, leadplant, purple poppy mallow and torch lily create a beautiful mix of summer oranges and violets
  • Sand lovegrass, pale purple coneflower, hummingbird mint, sage and Autumn Joy sedum offer winter texture and color
  • Little bluestem, rattlesnake master, gayfeather, yarrow and dwarf false blue indigo provide color and winter seedpods
  • In western Nebraska, consider pairing prairie zinnia, prairie dropseed, rabbitbrush, pineleaf penstemon and blue flax for year-long textural contrast and bold, long-lasting blooms

            For sunny areas with average to moist soil:

  • Goldenrod, switchgrass, pitcher sage, balloonflower and aromatic or New England aster have great autumn color
  • Pasqueflower, shortbeak sedge, dwarf spiderwort, prairie smoke and junegrass green-up and bloom in early spring

            For sun to part sun with wet soil:

  • Mountain mint, fox sedge, daylily, beebalm and Riddell’s goldenrod make for bold summer color

For shade to part shade with moist soil:

  • Sweet woodruff, wild ginger, variegated solomon’s seal, wild columbine and woodland phlox create attractive spring groundcovers

            For dry shade to part shade:

  • Oak sedge, bloody cranesbill, yellow corydalis, foam flower and epimedium offer beautiful summer color and texture

            Woody combinations:

  • Prairie Gold quaking aspen and Gro-Low sumac provide excellent fall color in sunny areas
  • Black Hills spruce and Isanti redtwig dogwood create winter interest
  • Apache plume and curl-leaf mountain mahogany have strong textural contrast and can withstand dry conditions (good choices for western Nebraska)
  • Serviceberry, arum and plumbago for spring and fall “wow” in shade
  • Deam’s viburnum and blue flag in wet areas for spring blooms, summer texture, fall color and winter berries

Thanks to Greg Simmons and Kim Todd of the University of Nebraska-Lincoln, Todd Faller of Faller Landscape & Nursery and Amy Seiler and Christina Hoyt of the Nebraska Forest Service for their time and ideas.

For photos of plant combinations: http://pinterest.com/nearboretum/plant-combinations-sun/