Polymnia spp.

leafcup

Asteraceae Eastern North America

Attracts Pollinators Attracts Butterflies

Native to North America

SunPart Shade – Full Shade

WaterMedium

HardinessZones 4–8

Overview

Polymnia spp. is a genus of tall, coarse herbs in the daisy family (Asteraceae), known as leafcups and native to eastern North America. Plants are robust perennials or biennials reaching 2-6 ft (0.6-1.8 m) tall, with stout, often sticky-hairy stems that branch in the upper part. The large opposite leaves are thin, broadly triangular to deeply lobed, and up to 12 in (30 cm) long, the upper ones clasping the stem with winged stalks. From summer into autumn the branch tips carry small daisy heads about 1-2.5 cm across, with short pale-yellow or whitish ray florets surrounding a yellow disc. The seed heads are small and dry. Polymnia canadensis grows in shaded, moist, often limy woods and ravines, while related species occupy similar rich, shaded ground. The genus tolerates deep shade better than most daisies. One limitation is the coarse, weedy look of the foliage and the sticky hairs that catch dust, and another is the modest size of the flowers relative to the large leaves.

Native Range

Polymnia spp. is native to eastern North America, ranging from Ontario and the Great Lakes south through the Appalachians and into the south-central United States. Plants grow in moist, shaded, often calcareous woodland, ravines, stream banks, and shaded roadsides.

Suggested Uses

Grown in shaded native plant gardens, woodland borders, and the margins of damp, lightly wooded ground where a tall, coarse-textured perennial is wanted. The plants fill shaded back-of-border positions that many daisies will not tolerate. Flowers and seeds draw small insects and birds.

How to Identify

Identify Polymnia spp. by its tall, sticky-hairy stems and very large, thin, opposite leaves that are broadly lobed and clasp the stem on winged stalks. The small daisy heads have only a few short, pale rays around a yellowish centre, looking modest against the broad foliage. A faint resinous scent and a preference for shaded, moist woodland help confirm it.

Appearance

Size & Dimensions

Height2' - 6'

Width/Spread1'6" - 3'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~8 weeks

Summer Fall

Flowering runs from midsummer into autumn, roughly July to September. The small pale daisy heads open in loose clusters at the branch tips over several weeks. Bloom is sparse compared with the bulk of the leafy stems.

Detailed Descriptions

Flower Description

pale yellow to whitish

Foliage Description

green

Growing Conditions

Sun Requirements

SunPartial Shade SunFull Shade

Requires 2-5 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 clay

Drainagemoist

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

1-2 years to flowering

Care & Maintenance

Care Guide

Polymnia spp. grows in part to full shade in moist, fertile, humus-rich soil, tolerating the limy ground of its native ravines at a pH of about 6.0 to 7.5. Steady moisture suits the large leaves, which wilt in dry, sunny positions. The genus withstands cold winters in USDA zones 4 to 8 and dies back to the ground each year. Plants grow quickly from seed and may self-sow where conditions are moist and shaded. Tall stems in exposed spots can flop and may need support. Slugs sometimes graze the young foliage.

Pruning

Stems are cut to the ground after they are killed by frost or once flowering and seeding finish. Cutting back before seed ripens limits self-sowing where the plants are not wanted to spread. New growth rises from the rootstock in spring.

Pruning Schedule

fall