Coleus can be grown in the sun if you grow the right varieties.

November 26, 2010

Most gardeners know coleus is a durable annual. But in the shade, right? Not anymore. In our trial gardens at the University of Georgia (UGA), I've evaluated more than 50 new varieties since the coleus revival 5 years ago. The best of them hold their vibrant colors and grow vigorously under the hot sun. This is true from Miami to Montreal.

Winning Varieties
I have been personally involved in the selection, naming, or distribution of the varieties I'm about to mention, so I know their names are correct. They should be found accurately identified in garden centers everywhere. You can't go wrong with any of them.


Sunlover series: Among the seven Sunlovers, 'Red Ruffles,' 'Rustic Orange,' 'Gay's Delight' (a "55-mile-per-hour plant"—it reaches its full size in just a few weeks), and dainty, low-growing 'Thumbellina' have always attracted the attention of visitors to our trial gardens and earned high marks for consistent performance from our team of evaluators. In 1997, 'Red Ruffles' won our Georgia Gold award, which we give each year to a few plants in our trials that are outstanding all season, defying heat, humidity, drought, rain, little old ladies, students, weekend football games, bugs, and diseases.

Solar series: Like the Sunlovers, the Solar varieties stay bright and upright through hot summer days in the sun. I love 'Solar Morning Mist,' with leaves that are white and green in the center and scarlet on the tip and edges, and 'Solar Sunrise,' with light green centers and purplish pink leaves. The serrated deep-green leaves of 'Solar Flair' make it my favorite of these varieties. It won our Georgia Gold award in 1996.

Ducksfoot series: Flattened foliage shaped a bit like ducks' feet gives this series its name. The standard variety in this group, 'Indian Frills,' has green leaves that are tinged with purple. The leaves of 'Purple' are a cool deep grayish purple. Both of these varieties are smaller in stature than the Sunlover and Solar varieties—the Ducksfoot duo get no taller than 18 inches high—and they also have smaller leaves, which makes them more drought tolerant than the others. Breeding continues with this group, and new choices (mostly in darker colors) are still emerging.

Independents: Here you'll find lots of varieties with whimsical, magical, and outrageous names. These are some of my favorites. I think 'Alabama Sunset' is unbeatable for its outstanding pastel colors and vigorous growth. Even in the shade, where its leaves turn almost completely red, it is eye-catching. 'Pat Martin,' which has elegant purple leaves that are edged with green, adds class to the gaudy independents. If you have a spot for a flashier plant, consider growing 'Leopard,' which is purple with green edges and white speckles.

Propagating Coleus
Growing new coleus plants from ones you have is easy. Here's how to do it:

  • When the temperature is above 60 degrees F, take terminal cuttings (the tops of actively growing stems) that are about 3 inches long and have two or three "nodes," or buds that will open into new leaves. Trim the cutting flush to the bottom node.
  • Place the cutting in a small pot filled with soil-less mix, such as a moist 3-to-1 ratio of perlite to peat. Cover the container with a plastic bag to maintain moisture and place it in a warm area (70 to 75 degrees F). The warmer the temperature, the faster the rooting process.
  • Roots will sprout within 10 days, and a well-rooted plant is ready for transplanting to your garden after 2 to 3 weeks.

Caring for Coleus
Coleus planted in compost-enriched garden soil that drains well will usually thrive with little attention. Your coleus will be even better with these techniques suggested in Rodale's Landscape Problem Solver.

For bushier coleus, pinch off flower stalks and other spindly stems.

Enhance coleus colors by spraying the plants with seaweed extract in late spring and once again in early summer.

If you find yellow stippling on the leaves of your coleus, it's not part of the beautiful variegated coloring of this plant: It's probably a sign of mites. As soon as you notice the first stippling of the leaves, spray your coleus plants early in the morning with a forceful stream of water to knock mites from the leaf undersides. Repeat daily for three days.

Small plants that display poor coloring may be infested with whiteflies. Look for these tiny, white-winged, moth-like insects on the undersides of coleus leaves. When a plant is bumped or brushed, they fly up, looking like flying dandruff. Control whiteflies by spraying infested plants with insecticidal soap every three to five days for two weeks.