Over 100 Japanese maple varieties being evaluated in LSU AgCenter trials with more to come. (Photo by Allen Owings)

Green-foliage Japanese maple in the Margie Jenkins Azalea Garden at the LSU AgCenter Hammond Research Station. (Photo by Allen Owings)

News Release Distributed 11/03/14

By Allen Owings
LSU AgCenter horticulturist

HAMMOND, La. – Japanese maples have the potential to be one of the most outstanding small trees for specimen plantings and focal-point use in residential landscapes in the Southeast. And fall and winter are the best time of the year to add Japanese maples to the landscape.

Normally Japanese maples do best in USDA hardiness zones 5-8. Louisiana is in zones 8 and 9, so being in the southern range of the recommended planting region can present some challenges. With proper planting and site selection, however, Japanese maples will do well in Louisiana.

When planting Japanese maples, select a partial-sun to partial-shade location for best results. Full sun will result in summer leaf burn on many varieties. A little more sun than shade, however, will provide enhanced leaf color.

Protection from windy conditions also needs to be considered. Soil should be well-drained but maintain some moisture, so be sure to select an ideal planting site. A slightly acid soil is recommended. Japanese maples are very shallow-rooted. Mulch with pine straw to protect the shallow root system from excessive drying out. Irrigate only as needed.

Variations in leaf color and shape are a unique horticultural characteristic of Japanese maples. You can find green-foliaged and red-foliaged varieties. Most of the green-foliage varieties have reddish or yellow fall color. Red-foliage varieties are most susceptible to sun scald during summer and early fall. Some of the finer-textured-foliage species are referred to as threadleaf forms.

Japanese maples have a slow growth rate, and most varieties will mature to a height of about 15-20 feet. Average width is 10-15 feet at maturity, but dwarf types also are available. Spreading forms grow wider than tall, and some varieties have a cascading, umbrella-shaped canopy.

Japanese maples need little care once established in the landscape. Prune them lightly in winter as needed during the first five years to maintain the desired shape and to remove competing branches. A light application of a slow-release fertilizer every couple years in early spring is recommended.

Many varieties of Japanese maples are available. Bloodgood, Fireglow, Crimson Queen and Burgundy Lace are some popular ones at garden centers in Louisiana.

The LSU AgCenter has initiated a Japanese maple evaluation and collection program at the Hammond Research Station. Over 100 varieties are currently planted, with an additional 100 varieties planned for the next few years. The AgCenter also is beginning the initial work on releasing three Japanese maple varieties with Louisiana historical significance.

You can see more about work being done in landscape horticulture by visiting 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 at both sites.

Rick Bogren