Aspidistra spp.: Cast Iron Plant

This document is part of a series originally written by Edward F. Gilman.

Introduction

Aspidistra is a genus that contains over 200 species native to woodland areas of Asia. The cast iron plant belongs to this genus. While Aspidistra elatior is the most common species of cast iron plant used in landscaping, there are various other species and cultivars with different growth dimensions, and leaf and flower colorations. Some cultivars are more readily available, while others may be found at specialty nurseries. The common name of this plant, cast iron, refers to this plant’s extreme hardiness in various conditions, including tolerating heavy shade, drought conditions, resistance to herbivores, and thriving in nutrient poor soils. This plant requires little care but should be located in the proper growing conditions.

The cast iron plant is an upright herbaceous perennial with a height and spread of 1 to 3 feet (Figure 1). It has large 18- to 36-inch-long oblong leaves that may be dark green or variegated, depending upon cultivar selection (Figure 2, Table 1). Cast iron plant produces a brown flower periodically throughout the year that emerges from the base of the stems (Figure 3). This plant grows in large, leafy clumps, and has a spreading growth habit. The glossy, coarse-textured leaves provide an excellent background for low flowering annuals or make effective mass plantings when allowed to spread by underground stems into a groundcover. It also makes a nice edging or filler plant in front of a shrub border. This plant may also be used in a container or grown inside as a houseplant, and cut foliage may be used for flower decorating. Cast iron plants should be kept out of direct sunlight, as too much sunlight will cause leaf burn.

General Information

Scientific name: Aspidistra spp.

Pronunciation: ass-pid-DISS-truh species

Common name(s): cast iron plant, Aspidistra, barroom plant, iron plant

Family: Asparagaceae

Plant type: perennial; herbaceous

USDA hardiness zones: 7A through 11B (Figures 4 and 5)

Planting month for zone 7: year-round

Planting month for zone 8: year-round

Planting month for zone 9: year-round

Planting month for zones 10 and 11: year-round

Origin: native to temperate Asia

Invasive potential: not considered a problem species at this time

Uses: container or above-ground planter; groundcover; suitable for growing indoors; accent; edging; cut foliage

Availability: generally available in many areas within its hardiness range

Description

Height: 1 to 3 feet

Spread: 1 to 3 feet

Plant habit: upright

Plant density: moderate

Growth rate: slow

Texture: coarse

Foliage

Leaf arrangement: emerges from the soil on a 7- to 12-inch petiole

Leaf type: simple

Leaf margin: entire

Leaf shape: oblong

Leaf venation: parallel

Leaf type and persistence: evergreen

Leaf blade length: 18 to 36 inches

Leaf color: green; white; variegated; dependent upon cultivar selection

Fall color: no fall color change

Fall characteristic: not showy

Flower

Flower color: brown

Flower characteristic: flowers periodically throughout the year

Fruit

Fruit shape: no fruit

Fruit length: no fruit

Fruit cover: no fruit

Fruit color: not applicable

Fruit characteristic: inconspicuous and not showy

Trunk and Branches

Trunk/bark/branches: typically multi-trunked or clumping stems

Current year stem/twig color: not applicable

Current year stem/twig thickness: not applicable

Culture

Light requirement: plant grows in the shade

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

Drought tolerance: moderate

Soil salt tolerances: poor

Plant spacing: 12 to 18 inches

Other

Roots: not applicable

Winter interest: no special winter interest

Pest resistance: no serious pests are normally seen on the plant

Use and Management

Cast iron plant tolerates a range of soil conditions, including nutrient poor soils. It is moderately drought tolerant; however, may require additional irrigation during drought conditions. Variegated cultivars of this plant require nutrient poor soil to retain coloration. Plant on 12- to 18-inch centers for a groundcover effect.

Cast iron plant should be sheltered from winter winds in USDA growing zones 8 and above as the leaves are very susceptible to winter burn. Old foliage may be removed in spring to provide fresh growth each year.

Propagation is by division of the matted clumps.

Design Considerations

Cast iron plant provides bold, architectural structure in areas of deep shade where few other plants can survive. Its upright, glossy, spear-shaped leaves create a striking vertical accent that contrasts beautifully with finer-textured companions. For a layered effect pair it with the delicate fronds of ferns, the soft mounds of mondo grass, or the broad, rounded leaves of Farfugiums. For a clean, contemporary look, plant cast iron plants in sweeping masses to form a lush, uniform groundcover that suppresses weeds and creates a sea of deep green.

Pests and Diseases

This plant has no pests of major concern and is resistant to insect pests. Disease issues include leaf-spotting.