Chelonopsis yagiharana (Yagihara Chelonopsis)

Chelonopsis spp.

false turtlehead

SunPart Shade – Full Sun

HardinessZones 6–9

Overview

Chelonopsis spp. is a genus of about sixteen herbaceous perennials and soft-wooded subshrubs in the mint family, Lamiaceae, distributed across temperate and subtropical eastern Asia from the Himalayas through China to Japan. Plants carry the square stems and opposite, toothed leaves typical of the family, growing 1.5-5 feet (45-150 cm) tall depending on species. The leaves are lance-shaped to ovate, 2-6 inches (5-15 cm) long, with serrated margins. From mid-summer into autumn, the upper leaf axils and stem tips produce tubular, two-lipped flowers 1-1.6 inches (2.5-4 cm) long in shades of rose-pink, mauve, and purple, often with darker spotting in the throat; the inflated corolla resembles that of Chelone spp., to which the genus is unrelated despite the similar name. Species grow naturally in mountain woodland, on grassy slopes, and along streams, generally in moist but freely draining ground. C. moschata and C. yagiharana are the species most often cultivated. The genus is little known in gardens outside Asia. One limitation is cold sensitivity: most species are reliably hardy only to about zone 6 or 7, and the subshrubby kinds can be cut back by hard frost. Plants reach flowering size within two to three seasons.

Native Range

Chelonopsis spp. is native to eastern and southern Asia, ranging from the Himalayas of India and Nepal through southwestern and central China to Korea and Japan. Species occupy mountain woodland margins, grassy slopes, and streambanks at moderate to high elevations.

Suggested Uses

Used in woodland-edge plantings, shaded borders, and moist mixed beds among ferns and shade perennials. Combines with Anemone spp. and Kirengeshoma spp. in part-shade schemes. Suited to collectors of Asian woodland flora.

How to Identify

Recognize Chelonopsis spp. by its square stems, opposite serrated leaves, and inflated tubular two-lipped flowers borne in the upper leaf axils. The corolla is rose-pink to purple, 1-1.6 inches (2.5-4 cm) long, with a hooded upper lip and a spreading lower lip marked with darker spots. The bell-shaped calyx that enlarges in fruit and the soft-wooded base of some species help separate it from related mints.

Appearance

Size & Dimensions

Height1'6" - 5'

Width/Spread1'6" - 3'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~6 weeks

Summer Fall

Flowering occurs from mid-summer into autumn, generally July to October. Flowers open a few at a time in the leaf axils over several weeks. In cooler climates bloom can be cut short by the first hard frost before all buds open.

Detailed Descriptions

Flower Description

rose-pink to purple

Foliage Description

green

Growing Conditions

Sun Requirements

SunPartial Shade SunFull Sun

Requires 3-6 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

Drainagemoist

Water & Climate

Water Needs

Medium

Frost Tolerance

hardy

Time to Maturity

2-3 years

Care & Maintenance

Care Guide

Grow Chelonopsis spp. in part shade to full sun in moist, humus-rich soil that drains freely. Consistent moisture during the growing season suits the genus, though waterlogged winter soil can rot the crown. A position sheltered from strong wind reduces damage to the tall, somewhat lax stems. In zones at the cold edge of its range, a winter mulch over the crown reduces losses. Plants need little feeding beyond an annual topdressing of compost. Slugs can damage emerging spring shoots.

Pruning

Stems can be cut back to the ground in late autumn after frost blackens the foliage, or left until early spring in colder areas to shelter the crown. On subshrubby species, winter-killed shoots can be removed in spring once new growth shows. A single pinch of tall species in early summer reduces flopping.

Pruning Schedule

fallearly spring