Daniel Gill, Merrill, Thomas A. | 4/19/2005 10:28:55 PM
By Dan Gill
LSU AgCenter Horticulturist
Perennials are an amazingly diverse group of plants.
Some perennials tower as tall as small trees, and others carpet the ground. Many produce attractive, colorful flowers, while others show off unique foliage. They grow in hot, dry sun or cool, moist shade. And they even populate our aquatic gardens.
A gardener could spend a lifetime acquiring and growing perennials and still not experience them all. Indeed, the efforts of researchers and adventurous gardeners constantly lead to the discoveries of new perennials that will thrive in our area.
Gardeners use the term perennial as an abbreviation for "hardy, herbaceous perennial." Hardy indicates that these plants will survive whatever cold we may have during winter, while herbaceous means plants they do not produce persistent, woody stems.
Perennials are plants that live for three or more years and, unlike annuals and biennials, do not die after flowering and setting seeds.
Some herbaceous perennials are evergreen and never go completely dormant. Others do go dormant, lose their leaves and essentially disappear at certain times of the year, usually winter.
For a herbaceous perennial to grow successfully in Louisiana, it must be able to deal with the extreme heat, humidity and rain we have during the summer. Fortunately, there are lots of wonderful perennials that thrive in Louisiana, including the one I’d like to tell you about today.
Rudbeckia ‘Goldsturm’ (Rudbeckia fulgida var. sullivantii ‘Goldsturm’) is an outstanding perennial that was recognized by the Perennial Plant Association as the 1999 Perennial Plant of the Year. It also was chosen as a Louisiana Select plant in 2000 by the Louisiana Nursery and Landscape Association and the LSU AgCenter.
Prolific flowering, low maintenance and proven perennial reliability are characteristics of Goldsturm rudbeckia. It is a great plant to consider for long-term performance in Louisiana landscapes.
As has happened more than once, this plant had its origins as a native U.S. wildflower that found its way to Europe and returned to us transformed into a garden flower. In 1937, Heinrich Hagemann found a planting of Rudbeckia fulgida var. sullivantii at Gebrueder Schuetz’s nursery in the Czech Republic. It had an especially attractive growth habit and produced an amazing number of flowers. It eventually was released in 1949 under the cultivar name ‘Goldsturm’ (which translates into English as "gold storm") and has been popular ever since.
Related to our native black-eyed Susans, Goldsturm blooms here anytime from late April to August and is a low-maintenance, long-lived perennial for full to part sun. It grows well in a wide variety of soil types and is somewhat drought tolerant, but will perform its best when planted in a prepared bed that has good drainage and is watered occasionally during dry periods. It is well adapted to the heat and humidity of the Louisiana summer and is rarely bothered by serious insect or disease problems.
The sturdy branched flower stalks produce numerous flowers, grow about 24-inches to 30-inches tall and do not require staking. The 3-inch to 4-inch daisy flowers are deep gold with a prominent black cone in the center – and they last a long time on the plant or when cut for indoor arrangements.
In the landscape, the brilliant golden-yellow flowers combine well with shades of blue or purple but also look good with any of the warm colors including orange, yellow, tomato red, bronze or mahogany. This plant looks wonderful combined with ornamental grasses, such as the variegated maiden grass (Miscanthus sinensis ‘Variegatus’), in the summer garden.
This time of the year it is best to plant larger, well established plants growing in at least 6-inch to 8-inch or, preferably, gallon-size containers. Plants growing in 4-inch pots, if available, will not put on much of a show planted this late but will grow and bloom beautifully in years to come. Planted now from larger containers, Goldsturm rudbeckia will bloom heavily this summer on good-sized plants and provide an excellent display in the landscape.
In a small bed or container, one plant can make quite a show, but in larger beds, especially those that will be viewed from a distance, I suggest planting a mass or drift of at least three to five plants for an impressive display. Space plants 12 inches to 18 inches apart, plant them at the same depth they were growing in the containers and mulch the area to control weeds and retain moisture. Water the newly planted rudbeckias deeply and regularly if the weather is hot and dry.
Deadhead individual flowers as they fade, and cut entire flower stalks back to the lower leaves as they finish. The attractive dark green foliage of Goldsturm rudbeckia is fairly evergreen here. Other than when they bloom, the plants have a rather low profile in the flower garden.
Consider planting Goldsturm rudbeckia in your flower garden. You simply won’t find a tougher, more reliable perennial for Louisiana gardens.
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.