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Pentalinon luteum Wild Allamanda, Hammock Viper's-tail

Edward F. Gilman, Ryan W. Klein, and Gail Hansen

Introduction

Wild allamanda grows as a vine-like shrub when it is young. Left to its own devices, it develops into a sprawling vine climbing over nearby shrubs, trees, and other structures. In this manner, it is not unlike the non-native allamanda. Yellow flowers about 2 ½ inches across are produced year-round on stem tips. Although the plant is not covered with flowers like the non-native allamanda, there are usually some flowers on the plant all year long.

Full Form - Pentalinon luteum: Wild allamanda, hammock viper's-tail.
Figure 1. Full Form - Pentalinon luteum: Wild allamanda, hammock viper's-tail.
Credit: Edward F. Gilman, UF/IFAS

 

Full Form - Pentalinon luteum: Wild allamanda, hammock viper's-tail.
Figure 2. Leaf - Pentalinon luteum: Wild allamanda, hammock viper's-tail.
Credit: Edward F. Gilman, UF/IFAS

 

Full Form - Pentalinon luteum: Wild allamanda, hammock viper's-tail.
Figure 3. Flower - Pentalinon luteum: Wild allamanda, hammock viper's-tail.
Credit: Edward F. Gilman, UF/IFAS

General Information

Scientific name: Pentalinon luteum

Pronunciation: pen-tuh-LYE-non LYOO-tee-um

Common name(s): wild allamanda, hammock viper's-tail

Family: Apocynaceae

Plant type: vine

USDA hardiness zones: 10B through 11 (Figure 4)

Planting month for zone 10 and 11: year-round

Origin: native to Florida

Invasive potential: aggressive, spreading plant

Uses: espalier

Availability: somewhat available, may have to go out of the region to find the plant

Shaded area represents potential planting range.
Figure 4. Shaded area represents potential planting range.
Credit:

Description

Height: depends upon supporting structure

Spread: depends upon supporting structure

Plant habit: spreading

Plant density: moderate

Growth rate: moderate

Texture: medium

Foliage

Leaf arrangement: opposite/subopposite

Leaf type: simple

Leaf margin: entire

Leaf shape: elliptic (oval)

Leaf venation: pinnate

Leaf type and persistence: evergreen

Leaf blade length: 2 to 4 inches

Leaf color: green

Fall color: no fall color change

Fall characteristic: not showy

Flower

Flower color: yellow

Flower characteristic: year-round flowering

Fruit

Fruit shape: unknown

Fruit length: unknown

Fruit cover: unknown

Fruit color: unknown

Fruit characteristic: inconspicuous and not showy

Trunk and Branches

Trunk/bark/branches: not applicable

Current year stem/twig color: brown

Current year stem/twig thickness: medium

Culture

Light requirement: plant grows in part shade/part sun

Soil tolerances: acidic; alkaline; sand; loam; clay

Drought tolerance: high

Soil salt tolerances: moderate

Plant spacing: 36 to 60 inches

Other

Roots: not applicable

Winter interest: plant has winter interest due to unusual form, nice persistent fruits, showy winter trunk, or winter flowers

Outstanding plant: plant has outstanding ornamental features and could be planted more

Pest resistance: long-term health usually not affected by pests

Use and Management

Wild allamanda can be maintained as a shrub with periodic pruning to check its size. Cut the longest stems back inside the plant so new growth helps keep the shrub full. It makes a nice addition to the native landscape in tropical areas as a specimen, or it can be trained to grow onto an arbor or trellis. The vine will need periodic clipping to keep it from overtaking the trellis. A row of wild allamanda planted several feet apart can be maintained as a low hedge with regular clipping.

Although growth continues in the total shade, wild allamanda will flower best in full sun or partial shade. With tolerance to salty air and drought, it is nicely suited for sandy, coastal landscapes. Plants grow fine in alkaline soil.

Pests and Diseases

There appear to be few problems that limit the growth of wild allamanda.