When home gardeners see think about Coleus plants what may come to mind is the houseplant that their grandmother had in the parlor. Or the plant that they learned to root in water in an elementary school science experiment. Growing of coleus plants as houseplants and in the landscape has been done by home gardeners for many years. And, as with many different ornamental plants, its popularity has peaked and ebbed over the last 150 or so years that it has been in cultivation.
Considered a tender annual here in Cherokee County, Coleus is thought to originate from Southeast Asia where it grows as an herbaceous perennial. Classified as a member of the mint family with its square stem and opposite leaves, coleus is an easy plant to grow in full sun and partial shade without a lot of pest problems. Grown for its very colorful foliage this plant can be used as a container plant or in a landscape bed.
According to the National Gardening Bureau (ngb.org) during the Victorian period gardeners utilized coleus in bedding designs called “carpet gardening.” These complex landscape plantings were designed to be viewed from above. Most of the time, however, you see Coleus plants used as container plants, combining shades of pink, yellow, green, red, and maroon used as a focal planting to highlight porches and patios. If you are looking for various container planting designs using Coleus, check on the Internet or some of the popular gardening magazines for ideas.
Also known as painted nettle or flame nettle, Coleus provides a literal rainbow of color combinations in its foliage depending on cultivar. These colors can range from yellow, red, orange, dark maroon, brown, pink, white and cream. To add to the variety the leaf colors can appear in solid colors, streaks, flecks, splashes or with distinctive color displays on the leaf margins or veins.
In addition, Coleus plant leaves come in variety of leaf forms and textures. Depending on the cultivar, the leaf form can range from exceptionally large to small, elongated, lobed, duck foot shaped, and scalloped. Mature forms of the plants can vary from smaller types that will reach only 1 foot tall to tall bushy types of 3 feet. There are also spreading forms that do well in wall plantings and hanging baskets.
In the past use of Coleus has usually been restricted to shady, dappled light or semi-shady areas. Recent breeding introductions such as the “Stained Glassworks”, “Wizard”, “Versa” and Marquee series, have been selected for increased sun and heat. If the variety has the word Sun it, like ‘Alabama Sunset’ or ‘Burgundy Sun’, it will do well in sunny locations.
Color intensity may be affected by sunlight, heat, sensitivity, and other conditions. However, if you grow a variety that does best in a semi-shaded environment, the sun will beach out the leaf color and they will lose their effect in the landscape. If you want the best leaf coloration of Coleus plants place them where they will get the morning sun and some degree of afternoon shade. Coleus can be easily grown from either stem cuttings or seeds.
Coleus do best when planted in well-drained soil or in containers which provide adequate drainage. Plants suffering from “wet feet” will be stunted, leaves will turn a muddy brown, and leaf, margins will be scorched. Plants in poorly drained locations will also suffer from stem and root rot. On the other hand, Coleus will quickly wilt if they are exposed to dry conditions so there is no guessing whether the plant is thirsty! When planting coleus transplants be sure to water coleus thoroughly at planting. I like to recommend that you use a half strength water soluble fertilizer solution. If the fertilizer label says two tablespoon of fertilizer per gallon of water only use one tablespoon. With heavy clay soils don’t overwater but do not allow plants to dry out. During the first 7 to 10 days, keep root balls moist but not overly wet. Thereafter, water when the entire top inch of soil is dry (check below the soil surface every three to five days). Use a soaker hose or drip system to deliver water to the base of the plant without wetting the foliage.
Coleus plants are tolerant of a wide range of acid to alkaline soils. Pest wise occasionally you may have insect problem like aphids, mealybugs, or whiteflies with the plants. These pests can easily be treated with a non-toxic soap spray. Happy Gardening!