Morella cerifera: Southern Waxmyrtle

Introduction

Multiple, twisted trunks with smooth, light grey bark, aromatic, dark green leaves, and clusters of blue-gray, waxy berries on female plants which are attractive to wildlife are just some of the reasons waxmyrtle is such a popular landscape plant. Most specimens form a multi-stemmed, open, rounded canopy of weak trunks and branches. This rapidly-growing, small, evergreen native tree is capable of reaching a height of 25 feet with an equal spread but is usually seen in the 10 to 20-foot range. Sometimes used as a large shrubbery screen, waxmyrtle is ideal for use as a small tree, the lower limbs removed to reveal its picturesque form. One, or several clustered together, provide pleasing dappled shade for terraces or patios.

General Information

Scientific name: Morella cerifera

Pronunciation: more-EL-la  ser-IF-er-uh

Common name(s): waxmyrtle, Southern waxmyrtle, southern bayberry

Family: Myricaceae

USDA hardiness zones: 7B through 11 (Fig. 2)

Origin: native to the Gulf and Atlantic coastal states from east Texas to Florida, and north to New Jersey, in addition to the Bahamas, the Caribbean, and Central America

UF/IFAS Invasive Assessment Status: native

Uses: screen; deck or patio; hedge; specimen; street without sidewalk; trained as a standard; container or planter; reclamation; parking lot island < 100 sq ft; parking lot island 100-200 sq ft; parking lot island > 200 sq ft; sidewalk cutout (tree pit); tree lawn 3-4 feet wide; tree lawn 4-6 feet wide; tree lawn > 6 ft wide; highway median; bonsai

Description

Height: 15 to 25 feet

Spread: 20 to 25 feet

Crown uniformity: irregular

Crown shape: vase, round

Crown density: moderate

Growth rate: fast

Texture: fine

Foliage

Leaf arrangement: alternate (Fig. 3)

Leaf type: simple

Leaf margin: entire, serrate

Leaf shape: spatulate, oblanceolate, oblong

Leaf venation: pinnate

Leaf type and persistence: evergreen, fragrant

Leaf blade length: 1 to 6 inches

Leaf color: dark green

Fall color: no color change

Fall characteristic: not showy

Flower

Flower color: pinkish-brown catkins

Flower characteristics: not showy; emerges in clusters Flowering: spring

Fruit

Fruit shape: round

Fruit length: 1/8 inch

Fruit covering: fleshy drupe

Fruit color: blue-gray

Fruit characteristics: attracts birds; not showy; fruit/leaves not a litter problem

Trunk and Branches

Trunk/branches: branches droop; showy; typically multi-trunked; no thorns

Bark: light gray to almost white, dotted with lenticels when young, then becoming smooth or almost smooth with age

Pruning requirement: needed for strong structure

Breakage: susceptible to breakage

Current year twig color: brown, gray

Current year twig thickness: thin

Wood specific gravity: unknown

Culture

Light requirement: full to partial shade

Soil tolerances: clay; sand; loam; alkaline; acidic; wet to well-drained

Drought tolerance: moderate

Aerosol salt tolerance: high

Other

Roots: not a problem

Winter interest: no

Outstanding tree: no

Ozone sensitivity: unknown

Verticillium wilt susceptibility: unknown

Pest resistance: resistant to pests/diseases

Use and Management

Very tough and easily grown, waxmyrtle can tolerate a variety of landscape settings from full sun to partial shade, wet swamplands or high, dry and alkaline areas. Growth is thin in total shade. It is also very salt-tolerant (soil and aerosol), making it suitable for seaside applications. It is adapted to parking lot and street tree planting, especially beneath powerlines, but branches tend to droop toward the ground, possibly hindering flow of vehicular traffic if not properly trained and pruned. Set them back from the road if used as a street tree so drooping branches will not hinder traffic. Removing excess shoot growth two times each year eliminates the tall, lanky branches and reduces the tendency for branches to droop. Some landscape managers hedge the crown into a multi-stemmed dome-shaped topiary. Plants spaced 10 feet apart, maintained in this manner, can create a nice canopy of shade for pedestrian traffic.

Plants should be watered well until established and will then require no further care. The only drawback to the plant is its tendency to sprout from the roots. This can be a nuisance as they need to be removed several times each year to keep the tree looking sharp. However, in a naturalized garden this thick growth could be an advantage, since it would provide good nesting cover for wildlife. Only female trees produce fruit provided there is a male nearby, but seeds do not appear to become a weed problem in the landscape.

The cultivar ‘Pumila’ is a dwarf form, less than three feet high. Myrica pensylvanica (Morella pensylvanica), northern bayberry, is a more cold-hardy species and the source of wax for bayberry candles.
Propagation is by seeds, which germinate easily and rapidly, tip cuttings, division of the stolons or transplanting wild plants.

Pests

Caterpillars and mites may occasionally attack the foliage. Webworms common in some landscapes—prune to remove infestation.

Diseases

Cankers may form on old branches and trunks and kill them. Also, a lethal wilt disease caused by the fungus Fusarium oxysporum and Fusarium spp. has been recently noted attacking waxmyrtle plants in central and south Florida. The vascular tissue is irregularly stained purple but not decayed as a result of the disease. Root injury and nitrogen fertilization encourage the disease.

References

Koeser, A. K., Hasing, G., Friedman, M. H., and Irving, R. B. 2015. Trees: North & Central Florida. University of Florida Institute of Food and Agricultural Sciences.

Koeser, A.K., Friedman, M.H., Hasing, G., Finley, H., Schelb, J. 2017. Trees: South Florida and the Keys. University of Florida Institute of Food and Agricultural Sciences.