Arnoglossum plantagineum (prairie Indian plantain)

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Arnoglossum spp.

Asteraceae Eastern and central North America

Attracts Pollinators Attracts Butterflies Drought Tolerant

Native to North America

SunFull Sun – Part Shade

WaterMedium · drought-tolerant

HardinessZones 4–8

Overview

Arnoglossum spp. is a genus of about eight tall herbaceous perennials in the daisy family, native to North America and formerly placed in Cacalia spp.. Plants grow from a fibrous crown or short tuber and reach 36-108 inches (90-270 cm) tall in flower. Basal leaves are large and long-stalked, 4-12 inches (10-30 cm) long, their shape ranging from triangular and toothed in A. atriplicifolium, which has a whitish waxy underside, to oval with parallel veins in A. plantagineum. Stem leaves reduce in size upward along grooved or angled stems. The flower heads contain only tubular disc florets, white to cream, with no ray petals, gathered in flat-topped clusters from midsummer into early autumn. Seeds are dry one-seeded fruits tipped with white bristles, carried on the wind. Growth is upright and largely unbranched until the flower cluster. Plants form slowly expanding clumps and are deep-rooted once established. The flower heads are small, and the tall stems can lean in exposed sites or in rich soil.

Native Range

Native to eastern, central, and southeastern North America, from the Great Plains east to the Atlantic. Grows in tallgrass prairies, wet meadows, open woodlands, glades, and savannas, often in moist to seasonally wet soils.

Suggested Uses

Grown in prairie and meadow plantings, rain gardens, and the back of native borders, spaced 24-36 inches (60-90 cm) apart. Tolerant of wet ground, it is used at pond margins and in detention basins. The height places it behind shorter perennials.

How to Identify

Recognized by tall, often unbranched stems topped with flat clusters of small white to cream flower heads that lack ray petals. A. atriplicifolium has triangular, coarsely toothed leaves with a chalky white underside; A. plantagineum has smooth oval leaves with roughly parallel veins. Stems are grooved or angled, and the one-seeded fruits carry tufts of white bristles.

Appearance

Size & Dimensions

Height3' - 9'

Width/Spread1'6" - 2'6"

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~4 weeks

Summer Fall

Disc-flowered heads open from midsummer into early autumn, about July through September. Bloom lasts 3-5 weeks on a given plant. Flowering is earlier in the south and later toward the northern range. Moist soils sustain a longer display.

Detailed Descriptions

Flower Description

white to cream

Foliage Description

green, white-glaucous beneath in some species

Growing Conditions

Sun Requirements

SunFull Sun SunPartial Shade

Requires 4-10 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 Range5.5 - 7.0(Neutral)

357912

Soil Types

loam clay silt

Drainagemoist

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

2-3 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Plants grow in full sun to part shade in moist, fertile soil and tolerate seasonal wetness. Establishment from seed is slow, often taking 2-3 years to reach flowering size. Established clumps are deep-rooted and drought-tolerant but stay shorter in dry sites. Tall stems may lean in wind or rich soil without support. Few pests trouble the foliage. Clumps are long-lived and seldom need division.

Pruning

Flowering stems are cut to the ground in late autumn or early spring. Spent flower heads are removed before seed disperses to limit self-sowing. No routine pruning is needed during the growing season.

Pruning Schedule

fallearly spring