1 - Pinching to remove flowers buds helps keep some coleus plants attractive.
Q. I bought a little 4-pack of different varieties of coleus plants two years ago in the spring. I grew them in pots, some outdoors, and some indoors, and they grew into huge beautiful plants. The outdoors plants came indoors in the winter with no problems for two winters. I have been able to start several new coleus plants from cuttings for friends.
My friends and I have a question. Some have heard the story that we are supposed to clip off all attempts at blooming so the plant will keep its leaves. Other say, "What? I have never heard of that!" Some of the varieties are more determined than others to bloom. So what is the real story? To interfere with the plant's attempt at reproduction, or just leave it be? We all want to keep the lovely leaves and encourage healthy growth.
San Fidel, NM
A. Standard gardening practice is to remove the flower stalks from coleus and other foliage plants to prevent the plants from diverting food into production of flowers and seeds instead of leaves. Since most gardeners propagate their coleus plants by means of cuttings as you have done, the seeds are not relevant for our purposes. Some gardeners do enjoy the challenge of growing new plants from seeds because they may produce new plants with different leaf colors. That is the good side of seed propagation. The bad side is that you may get some plants with a greater propensity to flower and make seed. As you mentioned, some plants are quicker to flower. In extreme cases, once they begin trying to flower it is difficult to get them to grow new healthy leaves and an attractive plant form.
When I was young I grew coleus plants that were passed from gardener to gardener, plants propagated from cuttings. Later I started some plants from a packet of seeds. I was very disappointed with the seed produced plants. They were attractive plants at first, but they persistently tried to bloom. Once they began to produce blossoms it was difficult to get them to grow new leaves. Each time I pinched the flowers from the end of the new shoot, it formed branches that would begin producing flowers before they had grown an inch. The result was a very unattractive plant. The good news is that many of the commercial growers of coleus have also observed this quick flowering trait, so now many are breeding coleus to be pretty, but slow to flower. In some cases they report that their new plants do not flower. That is even better since what we want as gardeners is the attractively formed plant with colorful leaves.
I would recommend that you pinch the flowering shoots as soon as they form. If you would like to try to see what new plants you get from seeds, be prepared to select from those seedlings only those plants that are slow to form flowers. Discard plants that form flowers quickly on side branches after you pinch the first flower stalk from the plant.
Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: firstname.lastname@example.org, office: 505-865-7340, ext. 113.
For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms.
Please copy your County Extension Agent and indicate your county of residence when you submit your question!