As summer draws to a close and autumn approaches, our gardens change from the vibrant colors of summer flowers to the muted colors of winter. But the garden in winter doesn’t have to be boring.
We can select plants to provide a lively transition with fall flowers, and a winter garden can have its own charms. There are many plants we can choose to help extend the garden season into the fall and winter.
When you talk about fall and late season flowers, most people immediately think about garden mums. Yes, garden mums are a great plant for fall color — and we do use a lot of them on the Penn State campus — but they are not the only option. There are many other fall blooming herbaceous perennials. For example, some asters can fill in with the same effect as a garden mum and are more consistently hardy in our winters. The New England aster Symphyotrichum novae-angliae is a deer-resistant native perennial with yellow centers and blue-purple to lavender-pink ray flowers. There are superior cultivars available, including “Purple Dome,” a dwarf with a nice mounding habit. Symphyotrichum novi-belgii, the New York aster, is another native aster for fall color in the garden. There are numerous cultivars of this plant, too. “Audrey” is a nice compact New York aster with lilac-pink flowers.
Anemone x hybrida, the Japanese anemone, is another excellent choice. In the fall, the Alumni Garden on campus comes alive with these striking white and pink flowers. “Alba” is an excellent cultivar with large white flowers and “Bressingham Glow” is a cultivar with pink semi-doubled flowers. There are some other great fall blooming flowers in the Alumni garden including Actea simplex, (autumn bugbane) with its white flowers and purple-black foliage and the groundcover Ceratostigma plumbaginoides (hardy plumbago) with nice blue-purple flowers and foliage that transitions to red in the late fall-early winter. Bergenia (pigsqueak) is another ground cover used on campus that transitions to red foliage in the fall and winter.
Some of the best herbaceous plants for winter interest are the ornamental grasses. Many people cut these back in the fall, but if you leave then up and cut them back in the spring instead, they can provide a great deal of winter interest in the garden. We use many different ornamental grasses on campus and most can provide some winter interest, but some of the best are the Pennisetums (fountain grasses). P. alopecuriodes is a perennial with striking bottlebrush flowers that will sparkle in the frost or catch a light snow. Miscanthus sinensis (Chinese silver grass) has both dwarf and large cultivars with feathery flower heads that provide winter interest. Calamagrostis x acutiflora (feather reed grass) is another ornamental grass with tall erect flowering stems, in this case with a feather-like flower spike that persists throughout the winter.
Campus gardens can be great places to go in the fall and winter to get ideas to help you keep your garden interesting throughout the year.
OLLI at Penn State — open to adults who love to learn — is offering more than 140 courses this fall semester. Robert Berghage will lead a course on Plants for Winter Interest. To receive a free fall semester catalog, call OLLI at Penn State at 867-4278 or visit olli.psu.edu.
Robert Berghage teaches herbaceous annual and perennial plant identification and use. He has been involved with the Penn State flower trials for more than 20 years.