Herbertia spp.

prairie nymph

Iridaceae

South America and the southern United States

Attracts Pollinators Container Friendly

Native to North America

SunFull Sun

WaterMedium

HardinessZones 7–10

Overview

Herbertia spp. is a genus of about six to eight small bulbous plants in the iris family, Iridaceae, native to temperate South America and the southern United States. Each corm produces a few narrow, pleated leaves and short stems 4-12 inches (10-30 cm) tall in spring. The flowers have three broad, spreading outer tepals in shades of lilac, violet, or blue, usually with a paler or white, often spotted center, and three much smaller inner tepals. Individual flowers last only a day, but a succession opens over several weeks. The North American H. lahue, called prairie nymph, grows in damp grassland and prairie along the Gulf Coast. After flowering the foliage dies back and the corms rest through summer. Because each bloom is so brief, the plants are easy to overlook except on sunny mornings when the flowers are open.

Native Range

Native to temperate South America, including Argentina, Uruguay, southern Brazil, and Chile, with H. lahue extending to the Gulf Coast of the southern United States. Plants grow in seasonally moist grassland, prairie, and open damp ground.

Suggested Uses

Used in rock gardens, bulb frames, and seasonally moist meadow plantings, set 3-6 inches (8-15 cm) apart in groups. The spring flowers draw early bees on sunny mornings. Container culture suits the brief, low-growing display where it can be viewed closely.

How to Identify

Recognized in spring by low, pleated, grass-like leaves and short stems bearing flowers with three large, outward-flaring tepals in lilac to violet-blue over a paler, spotted throat. The flowers open in morning sun and collapse by afternoon. The cormous rootstock and one-day flowers distinguish it from larger, longer-lasting irises.

Appearance

Size & Dimensions

Height4" - 1'

Width/Spread4" - 8"

Colors

Flower Colors

Foliage Colors

Bloom Information

Bloom Period

~3 weeks

Spring

Flowering occurs in spring, generally March to May depending on climate. Each flower lasts a single day, opening in morning sun, but new buds continue over several weeks. Bloom is heaviest after a moist winter and cool spring.

Detailed Descriptions

Flower Description

lilac to violet-blue with a paler center

Foliage Description

green

Growing Conditions

Sun Requirements

SunFull Sun

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

Medium

Frost Tolerance

hardy

Time to Maturity

1-2 years from seed to flowering

Care & Maintenance

Care Guide

Plants grow in full sun and well-drained soil that stays moist through the spring growing season. The corms are watered during growth and flowering, then kept drier as the foliage dies back into summer dormancy. Hardy forms such as H. lahue tolerate light frost, roughly to USDA zone 7, while South American species are more tender. Heavy, wet soil in the dormant season can rot the corms. Plants increase by offset corms and by self-sown seed where conditions suit. Crowded clumps are lifted and divided during dormancy.

Pruning

No pruning is needed beyond removing spent flower stems if seed is not wanted. The dying foliage is left in place to replenish the corm before it withers. Seed heads can be left to ripen for self-sowing.