The colors that are seen when sunlight is split by a prism are sometimes called the spectral colors. These are red, orange, yellow, green, blue, indigo, and violet. These ROYGBIV colors are often reduced to three red, green, and blue-violet which are the primary colors for the additive color system (light).
Growing coleus from seed. Coleus seedlings are abundant with varying shades of color from the moment they pop through the earth. Their vibrant colors are intensified when grown under fluorescent lights. An abundance of light is a must if you propagate coleus indoors in January.
Planting and Care. Coleus has long been considered a shade plant but the best leaf color is achieved with morning sun and some degree of afternoon shade. Many varieties do well in both shade and part-sun. Some can take quite a bit of sun as long as they are not allowed to dry out.verwintering coleus plants as houseplants is another way to get more plants. Temperatures near 70 degrees F. are required. Rotate plants and pinch back as needed to maintain form. Use grow lights to provide adequate light. By planting a single variety, such as Redhead, you can get dramatic effects.