Iudexvivorum, no rights reserved (CC0) · Wikimedia Commons

Asystasia spp.

Coromandels

Acanthaceae Tropical Africa and Asia

Attracts Pollinators Attracts Butterflies Drought Tolerant Container Friendly

SunFull Sun – Part Shade

WaterMedium · drought-tolerant

HardinessZones 9–11

Overview

Asystasia spp. is a genus of about 70 species of fast-growing herbs and soft subshrubs in the family Acanthaceae, native to tropical Africa and Asia. A widely grown species, A. gangetica, the Chinese violet or Coromandel, is a low, spreading plant used as a groundcover but also listed as an invasive weed across many tropical and subtropical regions. Plants form sprawling stems 1-3 ft (30-90 cm) high that root where the nodes touch the ground and can scramble higher through nearby shrubs. The leaves are opposite and oval, and the funnel-shaped flowers, about 1 in (2.5 cm) across, line up along one side of the stem in shades of white, cream, mauve, purple, and yellow depending on species and form. Flowering is heavy and prolonged in warm weather, and seed is shed freely, which is why several forms spread aggressively. The genus is frost-tender and killed by hard freezes, restricting it to warm climates or use as a fast summer groundcover. In its native range the young shoots of A. gangetica are eaten as a leafy vegetable.

Native Range

Native to tropical and subtropical Africa and Asia, including much of sub-Saharan Africa, India, and Southeast Asia. A. gangetica is widespread across the Old World tropics and has naturalized in the Americas, Australia, and on many islands.

Suggested Uses

Grown as a fast groundcover, bank cover, and hanging-basket plant in warm climates and as a summer filler in cooler ones, spaced 12-18 in (30-45 cm) apart. Where it is invasive, contained beds or containers are used to limit its spread.

How to Identify

Identify Asystasia spp. by sprawling, four-angled stems that root at the nodes, bearing opposite oval leaves. The funnel-shaped, five-lobed flowers are carried along one side of an upright spike and are about 1 in (2.5 cm) across, in white, cream, mauve, purple, or yellow, often with markings in the throat. The one-sided flower spike and rooting, scrambling stems help separate it from other tropical groundcovers.

Appearance

Size & Dimensions

Height1' - 3'

Width/Spread3' - 6'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~16 weeks

Summer Fall

In warm climates Asystasia spp. flowers over a long season from late spring through autumn, and nearly year-round in the tropics. The one-sided spikes open from the base upward, with new spikes following on fresh growth. Flowering is followed by capsules that fling seed some distance from the plant.

Detailed Descriptions

Flower Description

white, cream, mauve, purple, to yellow

Foliage Description

medium to deep green

Growing Conditions

Sun Requirements

SunFull Sun SunPartial Shade

Requires 4-8 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 clay sand

Drainagewell drained

Water & Climate

Water Needs

Medium

Frost Tolerance

tender

Time to Maturity

1-2 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Across the genus, Asystasia spp. grows in full sun to partial shade in most moist, well-drained soils, tolerating a pH from about 5.5 to 7.5. Plants grow quickly and tolerate heat, humidity, and short dry spells once established, slowing in drought and stopping in cold. They are frost-tender and suited to USDA zones 9-11, grown as summer annuals or groundcover elsewhere. Because stems root as they spread and seed disperses widely, plants can move beyond where they are set. Cutting back keeps growth dense and limits spread. Propagation is easy from cuttings or seed.

Pruning

Plants tolerate frequent cutting back and shearing, which keeps them dense and within bounds and removes seed-bearing stems. Trimming after each flush limits self-seeding and rooting spread. Stems pulled from moist soil often re-root, so prunings are removed rather than left in place.