Ixia spp.

corn lilies

Iridaceae

South Africa, primarily the Cape Floristic Region

Attracts Pollinators Attracts Butterflies Drought Tolerant Container Friendly

SunFull Sun

WaterLow · drought-tolerant

HardinessZones 8–10

Overview

Ixia spp. is a genus of about 50 to 80 cormous geophytes in the iris family, native to South Africa. Plants grow from small corms, producing fans of narrow, grass-like leaves 8 to 16 inches (20 to 40 cm) long and wiry flowering stems that reach 12 to 24 inches (30 to 60 cm). Each stem carries a spike of 6 to 20 star-shaped flowers, each 1 to 2 inches (2.5 to 5 cm) across, in white, pink, red, orange, yellow, and bicolored forms, many with a contrasting dark central eye. Flowers open in full sun and close in dull weather or in the evening. The genus is winter-growing and summer-dormant, dying back to the corm during the dry season, and the deciduous foliage reappears with autumn rains. Ixia spp. tolerates only light frost; in climates colder than USDA zone 8 the corms are lifted or grown in containers. The narrow leaves and thin stems give little wind resistance, and tall-stemmed forms bend under heavy rain or in exposed sites. Soil must drain freely, as corms rot in cold, wet ground during dormancy.

Native Range

Ixia spp. is native to South Africa, concentrated in the winter-rainfall Cape Floristic Region of the Western Cape, with a few species extending into the Eastern Cape. Most species grow on sandstone or clay slopes and seasonally moist flats that dry out in summer.

Suggested Uses

Grown in spring borders, gravel gardens, and rock gardens in mild-winter climates, and in containers where winters are cold. Cut stems are used in fresh arrangements, where the spikes open in sequence over several days. Massed plantings space corms 2 to 3 inches (5 to 8 cm) apart.

How to Identify

Identified by the flat fan of narrow, ribbed, grass-like leaves rising from a small fibrous-coated corm, and by the slender, wiry, often arching flowering stem. Flowers are radially symmetric with six spreading tepals fused into a short tube at the base, arranged in a one-sided spike. Many species show a dark or differently colored central blotch. The wiry stem and one-sided flower spike separate Ixia spp. from related Cape genera such as Sparaxis spp. and Tritonia spp..

Appearance

Size & Dimensions

Height1' - 2'

Width/Spread4" - 6"

Colors

Flower Colors

red

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~3 weeks

Spring

Across the genus, flowering runs from early to late spring, mainly September to November in the native range and April to June in Northern Hemisphere cultivation. Each spike opens over 2 to 3 weeks, with individual flowers lasting several days. Blooms open in direct sun and close in shade or overcast conditions.

Detailed Descriptions

Flower Description

white, pink, red, orange, yellow, often with a dark central eye

Foliage Description

green

Growing Conditions

Sun Requirements

SunFull Sun

Requires 6-10 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 Range6.0 - 7.5(Neutral)

357912

Soil Types

loam sand

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

tender

Time to Maturity

Flowers in the first or second spring from a corm

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Grow in full sun and sharp-draining sandy or loam soil. Corms are planted 2 to 3 inches (5 to 8 cm) deep in autumn for spring bloom. Water during the winter growing season and withhold water once foliage yellows in late spring, keeping corms dry through summer dormancy. In USDA zones 8 and warmer corms overwinter in the ground; in colder zones they are lifted after foliage dies down or grown in containers moved under cover. Corms left in cold, wet soil during dormancy are prone to rot. Clumps multiply by offsets and can be divided when dormant.

Pruning

No structural pruning is needed. Spent flower spikes are removed after bloom, and yellowing foliage is left intact until fully dry so the corm can reabsorb nutrients. Cutting foliage while still green reduces corm size and the next season's flowering.