Decision time regarding your coleus
We find ourselves in the first week of the season with nighttime temperatures below 50°. Gardeners will have already begun the annual ritual of preparing the garden for cold weather, so it’s time to focus on your coleuses.
First, orthography. On my deck are eight coleus plants, which means I have eight coleuses. Regarding arithmetic, somebody counted and there are about 300 species of coleuses in the world depending on whom you ask. Geographically, coleuses are native perennials in southern Asia with the strongest presence in Sri Lanka and Indonesia, though they are grown throughout the moderate regions of the world as annuals.
Coleuses are members of the mint family. Yep, cousins to spearmint, sage and basil, though only a few species are edible. Coleus esculentus, also known as the kaffir potato, has been grown for edible tubers for thousands of years in Africa, and some folks mill the tubers into flour. I grew a coleus variety from Central Africa for the edible leaves and used them like more familiar potherbs such as spinach or lambsquarters.
Most coleuses, however, are grown for their vibrant colorful leaves. Traders and horticulturists introduced them to Europe in the mid-19th century, and Victorian aristocrats paid top dollar for the exotic plants during “coleus fever” until the fad faded. Plebeians like us carried forward an appreciation of the simple elegant beauty of the leaves, and popularity rebounded for coleuses during the past forty years because plant breeders created new varieties with ever-diverse colors and patterns.
In early summer, a veteran coleus grower gave me a jar with six differently-colored coleus stems in water. Soon enough the stems sprouted roots, and I poked them into loose soil in pots on a semi-shady deck. They have prospered, but the time has come to act on their behalf. A coleus plant is easy to maintain and cheerful as a vireo, but it won’t tolerate cold weather outdoors. Darn.
A coleus plant is easy to grow and maintain. You can plant coleus seeds or transplant seedlings outdoors once soil temperature is at least 60°. Some varieties might reach three feet tall and almost as wide, and colors range throughout the color palette with varied patterns and combinations.
I have one that is a solid electric crimson, and others are variegated. They produce tubular flowers from mid-summer to early autumn, but pinching off the flowers allows for a bushier plant with more leaves. However, hummingbirds and pollinators might visit the flowers, so you choose.
Coleuses are happiest in loose, well-drained soil with enough occasional watering to keep roots moist. Some varieties can handle full sun, but most prefer partly shady hangouts. All these conditions apply to plants in pots and planter boxes, as well.
But what to do when cold weather arrives? Coleuses will be the first to suffer from temperatures below 50°. The easiest solution is to bring pots inside near a window. They do best in bright indirect light.
Maybe you have only minimal space inside but love your coleuses and intend to keep them forever. Well… the veteran coleus grower told me I could follow a similar procedure I did when I first got the cuttings – take five-to-six inch cuttings, remove the lower leaves, place in a jar of water and wait ‘til roots sprout, then plant them in smaller pots till spring. Stems from some varieties can skip the water-soaking step and go directly into soil.
This will be my first coleus winter. The pots on the deck will come inside this evening, and I will do what they tell me as best I can. Will I try to keep them forever? First, I will try to help them through the winter. Envision wandering through a coleus forest… trippy!