Abrus spp.

rosary pea

Fabaceae

Tropical Africa, Asia, and the Americas

Attracts Pollinators Deer Resistant Drought Tolerant

SunFull Sun – Part Shade

WaterLow · drought-tolerant

HardinessZones 10–12

Overview

Abrus spp. is a genus of twining woody and herbaceous climbers in the pea family (Fabaceae), with about thirteen to eighteen species across the tropics of Africa, Asia, and the Americas. The widely naturalised A. precatorius, rosary pea, climbs 3–6 m (10–20 ft) by twining stems clothed in pinnate leaves of many small oval leaflets 1–2 cm (0.4–0.8 in) long. Pale pink to purple pea-flowers are carried in dense clusters, followed by short curved pods that split to reveal hard, glossy seeds, most often scarlet with a black eye. The seeds contain abrin, a highly toxic plant protein; ingestion of a single chewed seed can be fatal to humans and animals, and the foliage and roots are also poisonous. Abrus spp. grows quickly in heat and full sun on most soils and is regarded as an invasive weed in Florida, Hawaii, and many other warm regions, where it smothers native vegetation. The hard-coated seeds remain viable for years. Cool temperatures and frost kill the top growth, limiting it to frost-free and subtropical climates.

Native Range

Species of Abrus spp. are native to tropical Africa and Asia, with some in tropical America. A. precatorius is thought to originate in Asia or Africa and has spread through the tropics and subtropics worldwide, becoming naturalised and invasive far beyond its original range.

Suggested Uses

Grown in tropical gardens as a fast screening climber on fences and trellises, and historically used for its hard seeds in beadwork and jewellery. Its invasive spread and poisonous seeds restrict its use to controlled settings away from children, pets, and livestock.

How to Identify

Recognised by twining stems with pinnate leaves of numerous small, oblong leaflets, and by clusters of small pink to purple pea-flowers. The seed is diagnostic: hard, glossy, 6–8 mm (0.25–0.3 in) long, scarlet with a sharp black spot at the attachment point, held in splitting curved pods. The leaflets have a faint liquorice taste that gives one common name, but the plant is poisonous.

Appearance

Size & Dimensions

Height10' - 20'

Width/Spread3' - 6'

Reaches mature size in approximately 2 years

Colors

Flower Colors

pink

purple

Foliage Colors

green

Bloom Information

Bloom Period

~8 weeks

Summer Fall

Abrus spp. flowers through the warm, wet season, generally summer into autumn and nearly year-round in equatorial climates. The small pea-flowers open in dense axillary clusters over several weeks. Pods ripen weeks later and split to expose the scarlet-and-black seeds, which persist on the plant.

Detailed Descriptions

Flower Description

pink to purple

Foliage Description

light green

Growing Conditions

Sun Requirements

SunFull Sun SunPartial Shade

Requires 6-12 hours of direct sunlight daily

• Full Sun: 6+ hours of direct sunlight

• Partial Shade: 3-6 hours of direct sunlight

• Full Shade: Less than 3 hours of direct sunlight

Soil Requirements

pH Range5.5 - 7.5(Neutral)

357912

Soil Types

loam sand clay

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

tender

Time to Maturity

1-2 years to flowering

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Abrus spp. grows in full sun to light shade on a wide range of soils, from sand to clay, and tolerates poor, dry ground once established. It needs frost-free conditions, as temperatures near freezing kill the top growth. A soil pH of about 5.5 to 7.5 suits it, and the twining stems need a fence, trellis, or host plant to climb. Growth is rapid and can overrun supports and nearby plants. All parts are poisonous, and the seeds contain abrin that stays toxic in dried and decorative material. The hard seed coat lets seed survive in soil for years.

Pruning

Abrus spp. is cut back to control its spread rather than for shape. Stems can be cut to the ground at any time, and in frost-free areas they resprout from the base. Removing pods before they split limits self-seeding and the spread of the toxic seeds.