Daniel Gill, Merrill, Thomas A.
Get It Growing News For 05/04/07
LSU AgCenter Horticulturist
Successfully creating colorful flower beds and container plantings for summer depends a lot on which plants you choose. Fortunately, we have many attractive and colorful heat-tolerant plants to do the job.
Much of the research the LSU AgCenter does on bedding plants is carried out by Dr. Allen Owings in trials at the Burden Center in Baton Rouge. This research evaluates the performance of different types of bedding plants and also compares different varieties of the same bedding plants in typical South Louisiana growing conditions.
Here are some of the best performers from the LSU AgCenter’s Burden Center trials to consider as you make decisions on what to put in your garden. These plants can be planted throughout the summer.
The typical garden zinnia (Zinnia elegans) that many of us are familiar with has more than its share of insect and disease problems, and this often leads to disappointment in mid- to late summer – when the plants succumb to these pests.
A different species of zinnia, however, called the narrow-leaf zinnia (Zinnia angustifolia) is far more insect- and disease-resistant and rarely has major pest problems. It is a low-growing, sprawling plant that produces multitudes of 1-inch single daisy flowers in orange, yellow and white, all with gold centers. The Crystal series, with more compact, uniform plants, is an improvement over the species. The Star series also is excellent, though less uniform. Performance in sunny areas is really outstanding, and the plants reliably hold up through the intense heat and rain of summer.
Profusion zinnias are the result of crossing common zinnias with narrow-leaf zinnias. The Profusion zinnias have received top marks in performance at Burden. They produce short, compact, ball-shaped plants that are covered with flowers through the summer. The flowers are larger and come in more colors than narrow-leaf zinnias, but the plants have inherited the pest resistance of that parent. The colors currently available are Profusion White, Profusion Orange, Profusion Cherry, Profusion Fire (orange-red) and Profusion Apricot.
Torenia, or wishbone flower (Torenia fournieri), has been one of my favorite summer bedding plants for a long time. You simply can’t beat their reliable performance in sun to part-shade. The neat, compact plants stay under a foot tall and come in various shades of lavender-blue, purple, pink and white.
When Summer Wave torenia became available several years ago, a whole new type of torenia entered the gardening scene. Producing unusually large flowers of medium lavender-blue, the plants possess a vigorous low-spreading habit. One plant can easily cover a 2-foot-by-2-foot area (or larger), and they never stop blooming until the first frost. Other colors are available these days, such as Pink Moon (light lavender pink) and Amethyst (reddish purple). And Proven Winners has released the Catalina torenia series, which look like they will be very similar.
Many of us have long been familiar with perilla (Perilla frutescens). The most commonly grown type has aromatic foliage that is ruffled and dark purple, and it can be used as a culinary herb as well as an ornamental. A new variety called Magilla perilla is very different and rapidly becoming popular. The dark purple leaves are highlighted by an area of vivid magenta in the middle. It closely resembles coleus (both are in the mint family), grows to be 2 feet tall or more and thrives in full sun to part shade. The colors are more muted in shadier areas.
A wonderful plant called angelonia (Angelonia angustifolia) showed up in nurseries a few years ago and performs beautifully in sunny beds. Angelonias are outstanding performers in the summer flower garden and will bloom until first freeze. They may even survive mild winters in protected locations and bloom another year. Look for AngelMist and Carita series, which come in a variety of colors. Perhaps the best angelonia is the new Serena series. Plants are more compact and bloom more than other types.
Coleus, which had always been used in shady beds, began to be part of our sunny gardens with the release of new sun-tolerant types in the 1990s. This trend has continued, and virtually all the new coleus varieties released in recent years have been sun-tolerant. Bucking the trend, however, is the new Kong series of coleus. Kong coleuses sport leaves far larger than other types of coleus and come in five different colors. They are not adapted to sun and must be planted where they get some shade to do their best. The bold texture and bright colors of the large leaves make a dramatic addition to shady beds.
Get It Growing is a weekly feature on home lawn and garden topics prepared by experts in the LSU AgCenter. For more information on such topics, contact your parish LSU AgCenter Extension office or visit our Web site at www.lsuagcenter.com. A wide range of publications and a variety of other resources are available.