As most gardeners know, fall is a good time to analyze the success of gardens, plus note areas which could be improved next year. If you have noticed that there are a few weeks here and there in the growing season with very few flowers in your beds, the reason might be that you have a preponderance of short-season bloomers. Take peonies, for instance. They can often be spotted in early to mid-June, the branches bent over with huge, heavy flowers. (Some gardeners stake them, but they seem to look best in their natural state; a lovely reminder of the generous outpouring of nature.) When peonies get going, they give off a delicious scent in addition to soft, voluptuous explosions of blooms. However, in a few short weeks they are spent. So, in order to enjoy blooms at any moment of the season, consider adding additional perennials to your landscape, which can have long blooming seasons of six to eight weeks.
By Gerry Hofmann
Colorado State University Extension Master Gardener in Larimer County
The simplest way to have more blooms in the garden is by planting something which is known to have a succession of blooms over time. Even as the first blooms are beginning to fade, new flowers are opening; this process repeats itself long enough to last several weeks. For instance, the blossoms of Hibiscus syriacus (also known as Rose of Sharon) open in such a way as to have several lovely 2″ soft blue trumpet flowers at any given time while the older ones are dying off. Hibiscus often leafs out quite late, to the point where some gardeners might think it isn’t coming back! It blooms from mid-summer into autumn.
Gypsophila elegans, commonly known as baby’s breath, is a good example of a plant that crosses over seasons, from early summer to early autumn. A tiny-flowered plant that prefers our alkaline soil and often drought-like conditions, its billowy delicacy provides an often much-needed contrast in a garden from the larger and often bolder blooms of other plants. Give this charmer full sun.
Another late spring to early autumn performer is Geranium nodosum, one of several species known as cranesbill. A terrific part-to-full shade plant, even in dry conditions, it is a great spreading ground cover, self-sowing along the way. Cranesbill is also easy to pull if it gets out-of-hand, since the roots appear to be shallow.
Early summer to early autumn can also be covered with the Geum hybrid “Lady Stratheden.” Smallish yellow ruffled flowers extend high above clumps of deeply-veined leaves. Another long bloomer “Mrs. J. Bradshaw” sports a rich scarlet flower. Geums are also available in a vivid orange (G. coccineum “Cooky”). These charmers will continue to perform well only if divided every other year, but are well worth the trouble.
For a good six weeks in late summer through autumn, a generous sprinkling of pinkish-lilac blooms grace the grapeleaf anemone (A. tomentosa ‘Robustissima’). It’s well worth it especially when you have had your fill of mums and asters! Finally, keep your season extenders well-watered and deadheaded for longer blooming. They’ll help you more if you help them too.
For additional information consult: “The Ever-Blooming Flower Garden: A Blueprint for Continuous Color” by Lee Schneller (2009). You can also visit the Colorado State University Extension website at www.ext.colostate.edu to find additional information on perennials.