Coleus are vibrantly hued foliage plants that provide constant color for containers and the landscape. All types of Coleus are now known as Plectranthus scutellarioides, so technically the earlier names such as Solenostemon scutellarioides, Coleus blumei, Coleus verschaftelti, or Coleus hybridus no longer exist. Coleus taxonomy seems to be forever in flux, so further changes might be down the road. Most of our plants labeled with the common name "Coleus" fall into the former Coleus blumei category, although some of the the trailing varieties were formerly labeled C. pumilus or C. rehneltianus. In the absence of a Coleus Society or registry for hybridizers, many Coleus cultivars have been claimed, renamed, and even patented by nurseries. Coleus are also very generous with producing "sports," which are mutations that can be propagated and sold as a new variety. The same sport may occur spontaneously at different nurseries and each might claim it as a new introduction and give it their own name. This causes a lot of confusion for Coleus collectors!
Native to Southeast Asia, Africa, India, and Sri Lanka, heat-loving Coleus are actually a herbaceous perennial in their native, tropical climate. Coleus are generally treated as an annual in the United States since there is no zone in the Continental U.S.A. where it is considered totally safe to grow Coleus outdoors through the winter. In some areas of the deep south it will not freeze every winter but eventually it will happen and the unprotected Coleus will be lost. Coleus can be over-wintered in pots in a warm house or greenhouse, but older Coleus plants may be more likely to bloom or harbor disease and pests. We recommended that you start new plants from cuttings or buy new Coleus in the spring.
Coleus are members of the Mint family (Lamiaceae), and have the characteristic square stems and opposite leaves of that group of plants. Coleus do not have the invasive growth habit of the herb Mint and are well-behaved in the garden. Some Coleus grow in an upright form, some grow in a mounding form, and some creep or trail. The leaves can be narrow or wide, round or ovate, and come in a wide range of interesting shapes and fancy leaf edges. The colored foliage for which Coleus are so famous can be red, pink, purple, green, yellow, orange, brown, and all shades in between.
Coleus flowers are quite tiny and cover a terminal flower spike. The flowers range in color from shades of purple to true blue to nearly white. While most people prefer that their Coleus don’t bloom, some like the flower spikes and several of them cut and bunched together can make a pretty Coleus bouquet. Coleus flowers are attractive to hummingbirds and can help draw them into the garden. Trailing varieties are the most likely of all the Coleus types to bloom, so they need occasional pinching to keep them bushy and bloomless. Coleus that are allowed to bloom unchecked may lose vigor, become weedy-looking, and go into decline.
Coleus History: Coleus are native to tropical areas of Southeast Asia, India, Africa and Australia, with the largest population being in Indonesia and Sri Lanka. Coleus found their way into Europe and later, America, by way of traders and botanists. While some accounts place Coleus in Europe as early as the 17th century, Dutch botanist Karl Ludwig Blume is often credited with naming and introducing Coleus to Europe nearly 200 years later as part of an extensive collection of plants he had studied while living on the Indonesian island of Java. Plant aficionados seized upon Coleus as the new “it” plant, and a sort of Coleus Fever swept through Victorian gardens, reminiscent of the Tulip Fever of the Netherlands in the 17th century. Coleus were a perfect choice for a Victorian garden technique called carpet gardening. A carpet garden consisted of flower beds laid out in elaborate patterns that were meant to be seen from a high window or balcony. The effect was that of a living Persian Carpet or tapestry.
As the popularity of Coleus grew, a new cultivar of Coleus could fetch an astonishingly high price from competitive aristocrats who wanted the most unusual specimens in their own gardens or conservatories. This plant lust ignited what was to be called “The Great Coleus Race” as hybridizers and hobbyists alike hurried to create new varieties to cash in on the craze. As fads always do, the popularity of Coleus subsided somewhat and the Coleus collecting hobby eventually trickled down to the common citizen, and most of the varieties we have today originate from snippets of Coleus that were lovingly over-wintered on the windowsills of generations of gardeners. That is fortunate, because when the commercial value of Coleus declined, so did the plant. Most seed houses carried Coleus seed throughout the years, but cutting-propagated Coleus seemed to disappear from commerce. By the middle of the 20th century Coleus seemed relegated to the benches of mass-produced flats in garden centers. They were grown from seed to be sold as bedding plants for shady gardens, and their short stature and propensity for bolting to flower had limited appeal for home gardeners. Many gardeners thought Coleus foliage to be gaudy and hard to mix with their flowers. What goes around, comes around, however, and in the 1990’s a few enthusiastic Coleus hybridizers began making inroads into the simultaneously expanding markets for both container gardens and bold-colored garden plants. After years of cultivating trendy pastel cottage gardens, people were starting to realize that color was a good thing and was not to be feared! Today Coleus are once again a desirable and fashionable garden plant. New, cutting-propagated Coleus varieties have been developed that bring this lovely Coleus out from the shadows and into the sun! Many of the new cultivars are slow to bloom, freeing up their caretakers from the tedium of pinching blossoms. (All Rosy Dawn Garden Coleus are cutting grown.)
Today, Coleus are wildly popular as container plants, and many people use groupings of containers to create container gardens. Container gardening makes it possible for almost anyone to grow Coleus, even if all you have is a small balcony or courtyard. Coleus also make outstanding hanging baskets for sheltered locations. For those who have no outside space for growing Coleus they can be grown as houseplants. As a houseplant, Coleus can survive but they need lots of light and humidity and good air circulation. Special care must be taken to watch for bug infestations when Coleus are kept indoors. If the gardener is lucky enough to have a heated greenhouse in which to over-winter their Coleus they will find that Coleus thrive in the humid, warm, greenhouse environment which mimics their native tropical climate. For more information on Coleus culture, please visit our Coleus Care webpage and our FAQ (Frequently Asked Questions) page. For more information on ordering Coleus please visit our Ordering Information page. For help in choosing which Coleus to buy please visit our Selection Guide. For in-depth articles on growing and enjoying Coleus please visit our blog at http://www.rosydawngardens.blogspot.com