Perennial verbena good landscape choice
Homestead Purple verbena has been named a Louisiana Super Plant for fall 2015 by the LSU AgCenter.
--LSU AgCenter/Allen Owings Photo
HAMMOND — One of the great flowers that continues to be popular in our Louisiana landscapes is perennial verbena.
Native verbenas grow along roadsides in Louisiana, and gardeners are familiar with many species of verbena. But the species Verbena canadensis and its hybrids are probably our best-performing. This herbaceous perennial is a reliable performer for two to three years following its original planting.
Early to mid-fall and from late winter into early spring are the best times of the year to plant perennial verbena. If you plant perennial verbena, the LSU AgCenter highly recommends the longtime favorite variety Homestead Purple. It’s the latest recipient of the Louisiana Super Plant designation.
Why Homestead Purple when we have many varieties of perennial verbena available?
The most popular and most readily available verbena in Louisiana, Homestead Purple is still the most proven landscape performer. It’s the first variety to flower in late winter or early spring. It’s the most cold hardy to the mid-teens. It’s the perennial verbena that looks best in the stressful summer months.
Homestead Purple has more abundant flowers at peak bloom. Large, deep purple flowers cover the dark green, wide-growing canopy. Other verbenas are promoted as more winter tolerant and more summer tolerant, but they are not. Homestead Purple is still better than the new perennial verbenas being sold today.
Homestead Purple was found at an old homesite in Georgia by horticulture professors from the University of Georgia. It quickly made its way to the commercial horticulture industry, and we sure are glad it did.
The AgCenter included Homestead Purple verbena in the Louisiana Select plant program in 1996, and it’s still a great choice today. It’s a shame that home gardeners don’t choose Homestead Purple as much these days even though other varieties now available have expanded the flower color range for these great plants. We feel we need to re-introduce the gardening public to this great variety.
When planting Homestead Purple perennial verbenas, place plants about 2-feet apart. This may sound like a considerable distance, but once growth begins, this will be an ideal spacing. These plants need a well-drained site, and full sun is preferred. Plants will do okay in partial sun but do not prefer more shade than sun. Soil pH is not critical — plants will do fine in slightly acid, neutral and even slightly alkaline soil. Mulch them with pine straw after planting, and fertilize with a slow-release fertilizer for best results.
Irrigate only to aid the plants in establishment and to assist them during excessively dry periods. Although perennial verbenas are very drought tolerant, they may develop powdery mildew or root rot or stem rot problems when overwatered or during periods of high rainfall.
Perennial verbenas flower best from late winter through spring and then in late summer through fall. Some flowers may appear in summer, but the hottest part of the year is not the prime time for this plant.
Pruning back plants after each flowering cycle is completed encourages new growth that will produce flowers when the next ideal time comes. Stem cuttings from the pruning process will root easily. Butterflies love perennial verbenas and will swarm the plant canopies in summer and fall.
LSU AgCenter research has found that most perennial verbenas come back in following years, but the plants may need replacing once every three to four years or so. They are not “long-term perennial” but are definitely worth planting and then enjoying several times during our gardening seasons.
When gardening this fall or early next spring, add Homestead Purple verbena to your landscape or to your container plant area. It’s a fabulous Louisiana Super Plant that you need to consider, and it’s one of the most enduring of the perennial verbenas.
You can see more about work being done in landscape horticulture by visiting the LSU AgCenter Hammond Research Station website at www.lsuagcenter.com/hammond. Also, like us on Facebook. You can find an abundance of landscape information for both home gardeners and industry professionals at both sites.
--By ALLEN OWINGS
LSU AgCenter horticulturist