Your coleus questions answered
The most important quality of a good coleus, says expert Ray Rogers, is that you can plant it and enjoy it without needing to make a constant fuss over it.
WHAT IS A “SUN COLEUS”?
The so-called “sun coleus” are varieties that tolerate a great deal of sun or even require it to show off their best coloration. Coleus are no longer plants strictly for shady sites – hybridizers and coleus enthusiasts continue to offer spectacular selections that will provide as much color as (or more than) many other sun-loving plants, including other annuals and many perennials.
Generally, grow the light-colored ones (those with white or pale pink or yellow in their leaves) in spots that receive only the first hour or two of morning sun. Most others do well with lots of morning sun (before it gets strong and hot), and some, including the sun coleus, luxuriate in all the sun you can throw at them. Experiment with your favorites to see what they can handle.
WHY SHOULD I REMOVE THE FLOWERS?
Flowering directs a plant’s energies toward seed production. Since we grow coleus for their colorful foliage, it makes sense to pinch out the flower buds as you notice them. Don’t wait until the flower clusters are big and unsightly.
Pinching will encourage the plants to send out more shoots and leaves, resulting in a denser, more colorful plant. Some coleus produce beautiful blue flowers, though, so you might want to stop pinching about six weeks before your expected first frost to enjoy them at the end of the season.
HOW DO I KEEP THEM OVER WINTER?
If you want to keep your favorites over winter for the next growing season, the easiest thing to do is to root some cuttings in water a month or two before your expected first frost.
Make the cuttings about four to six inches long, take off the lower leaves and flower buds, and place them in a glass of water. Roots will quickly form, and then it will be time to plant the cuttings in a pot containing well-drained potting mix.
Keep new plants warm and in as much sun as you can give them (under lights works, too). As the plants grow, you can repeat the process to make even more plants. Don’t plant them outside until all danger of frost has passed.
CAN I GROW ANY COLEUS FROM SEED?
Coleus are easy to grow from seed. However, almost all coleus grown from seed will probably not look like the plant from which it came, except for those intentionally produced by seed companies and offered for sale (such as Rainbow, Wizard, Carefree, and Black Dragon). Most of the coleus we grow today are kept “true” by raising them from cuttings taken from a parent plant.
WHERE CAN I BUY A SPECIFIC COLEUS? HOW MANY KINDS ARE THERE?
Start at your favorite local nursery, or ask your gardening friends for a cutting. Local gardening resources (such as a public garden or gardening expert) can provide help, too.
Several mail-order companies offer coleus; check out www.coleusfinder.org for a list of American and overseas sources. There are now hundreds of different coleus being grown and enjoyed worldwide.
WHICH IS YOUR FAVORITE COLEUS?
If I could grow only one coleus, it would be ‘Alabama Sunset,’ which offers changing combinations of chartreuse and red, depending on the amount of sun it receives. It grows well in gardens and containers and goes to flower reluctantly.
However, plenty of other coleus grow well and offer beautiful coloration, and they are waiting to become my next (and your) favorite.
Ray Rogers, is author of "Coleus" and "Pots in the Garden, both published by Timber Press.