Shoal Creek vitex flowers. (Photo by Allen Owings. Click on photo for downloadable image, then right click to save.)

News Release Distributed 04/26/13

By Allen Owings
LSU AgCenter horticulturist

HAMMOND, La. – One of the nicest small, flowering trees for Louisiana landscapes is the chaste tree or vitex (Vitex agnus-castus). Midspring through early summer is the main time for flowering on this increasingly popular plant.

Native to the Mediterranean region to central and western Asia, vitex has begun to create more interest among home gardeners and commercial horticulturists over the past ten years.

Trees reach heights of 15 feet in the landscape with a spread of 15-20 feet. At maturity, it has a rounded vase shape. By starting when they are young, they can be maintained as multiple-trunk specimens, similar to how crape myrtles can be shaped and maintained.

In most years, flowers appear in the Baton Rouge area the first or second week of May and last for about six to eight weeks. By July and August, we may pass the major blooming period for vitex trees. You can, however, get a second or extended bloom on these small trees by dead-heading the old flowers from the first bloom in late spring or early summer.

Vitex flowers are lavender blue, very showy and fragrant, and they attract bees. They form black fruit in late summer and early fall. A grouping of three plants together creates an attractive feature while single a specimen plant works fine as a focal point in the landscape.

Mature fruit can produce seedlings in landscaped areas. If you’re interested in welcoming wildlife to your gardens, as so many gardeners are these days, you’ll be glad to know that vitex flowers are also attractive to hummingbirds and butterflies, especially the bright yellow sulfur butterflies that flutter around the flowers. The yellow butterflies and lavender blue flowers look wonderful together.

Only a small number of named varieties are on the market. Shoal Creek is an outstanding vitex selection with superior characteristics compared with the standard type. That’s why it was named a Louisiana Super Plant in 2011. Another vitex variety to consider is Montrose Purple. And one called Lecompte originated from cuttings from a tree in central Louisiana.

For planting, select a well-drained, moist, fertile location. Sandy or silty soil would be much better than clay soil, which could create establishment problems. And avoid low spots that tend to hold soil moisture. Soil pH is not critical – anywhere from slightly acid to slightly alkaline should suffice. A full- to partial-sun planting site is needed for best results.

Vitex trees have a fast growth rate and high drought tolerance, and they can handle minor levels of soil salinity. Once in a while scale insects can be a problem, and root rot does occur in a poorly drained soil.

You can see more about work being done in landscape horticulture by viewing the LSU AgCenter Hammond Research Station website. Also, like us on Facebook. You can find an abundance of landscape information for both home gardeners and industry professionals.