How to choose
The variety of patterns is amazing, with solid colors, splashes, spots, streaks, spots, fringes and veins. Color intensity varies with sunlight, sensitivity to heat and other conditions. The term “sun coleus” refers to selections that tolerate more sun. The cultivars with dark leaves tend to tolerate more sun, while lighter cultivars need more shade to minimize leaf scorch. Morning sun and dappled afternoon shade tend to maintain consistent foliage coloration. Too little light promotes a weak-stemmed, less vigorous plant without the best color.
Another variable to consider is leaf structure, which includes large, small, twisted, oblong, scalloped, lobed, finger-like, and “duck feet” — they resemble webbed feet.
Coleus can be classified into three plant shapes: erect, rounded, and trailing. Frequent pruning, pinching, and trimming can help change shape, although the trailing varieties have great value on the edge of a planter or in a hanging basket.
plants and care
Coleus has long been considered a shade plant, but best leaf color is achieved with morning sun and some afternoon shade. Many varieties thrive in both shade and partial sun. Some tolerate quite a bit of sun as long as they are not allowed to dry out. Avoid soil that is too wet, which can cause leaf fall and promote disease. Plant coleus after all danger of frost has passed, when soil temperatures have warmed sufficiently and evening temperatures are above 60 degrees F. Fertilize the plants regularly with a water-soluble fertilizer, especially when growing in containers.
To maintain plant shape, prune every few weeks to prevent flowering. For best looks, pinch just above a row of leaves or a branch; leave no stub. Some gardeners leave the small flowers in place, but pinching them off is best to direct more energy into stem and leaf growth. Coleus left to flower can lose vigour, as the plant puts energy into seed production.
Get more plants
Growing Coleus from seed is relatively easy. Plan to sow them indoors eight to 12 weeks before the last frost date in your area. Since seeds need light to germinate, sow them on the surface. Be sure to monitor the water level carefully. For best results, use a seedstarting system and read How to Start Seeds.
Overwintering coleus plants as houseplants is another way to get more plants. Temperatures near 70 degrees F. are required. Rotate the plants and push back as needed to maintain the shape. Use grow lights to provide adequate light.
Design with Coleus
Use solid color Coleus varieties like Redhead and Lime Delight Premium Sun (both bred for the sun) to make a bold statement in the garden. Try multicolored varieties for “color echoes” that complement neighboring plants that have similar (or contrasting) flower and/or foliage colors. The repetition of certain Coleus colors and shapes can add unity and harmony to the garden. While a single specimen can add a “pop” of color, you should also consider the effects of mass planting. Foliage with lighter colors can illuminate shady locations, while dark colors add depth and contrast in the same environment.
Coleus in containers
Coleus do well in pots and planters as long as they are planted in free draining potting soil, fertilized regularly and given the right amount of sun. Avoid windy locations as coleus can break easily. Fertilize regularly during the growing season and stick to the amount recommended on the package. Coleus don’t show their best color when over-fertilized, so be conservative and consistent. You may want to consider self-watering planters, especially in sunny locations.
Coleus can also be used in traffic lights. Some of the selections below will flow nicely over the edge. Compact, bushy species can be used in the center of the basket. Remember that coleus are thirsty and a hanging basket can dry out quickly – choose a self-watering hanging basket for best results.