Chrozophora spp.

turnsole

Euphorbiaceae Mediterranean, Africa, and Asia

Attracts Pollinators Deer Resistant Drought Tolerant

HardinessZones 9–11

Overview

Chrozophora spp. is a genus of about ten annual and perennial herbs and subshrubs in the spurge family, Euphorbiaceae, native to the Mediterranean region, Africa, and southern and central Asia. Plants are low and branching, 8-24 inches (20-60 cm) tall, covered in grey, star-shaped (stellate) hairs that give the foliage a silvery, mealy look. The leaves are rhombic to ovate with wavy margins, and the plants are monoecious, carrying small yellowish male flowers and inconspicuous greenish female flowers on the same plant, followed by warty three-lobed capsules typical of the family. C. tinctoria, called turnsole or dyer's croton, yields a purple-to-blue dye that was historically used to color cheese, paper, and manuscript illumination. Plants grow on dry, open, often disturbed ground, in fields, and along roadsides in warm climates and behave as warm-season weeds in cultivated land. Like many spurges, the sap is acrid and can irritate skin and eyes. One limitation is the genus's weedy habit and lack of garden use, along with the mild toxicity of its tissues. Most are frost-tender plants of warm, dry regions.

Native Range

Chrozophora spp. is native to the Mediterranean basin, much of Africa, and southern and central Asia eastward to India. Plants grow on dry, open, disturbed ground, in fields, and along roadsides in warm climates.

Suggested Uses

The genus has little garden use and is grown mainly for the historical dye obtained from C. tinctoria and for botanical study. Elsewhere it occurs as a weed of warm, dry farmland and waste ground. It is seldom seen in ornamental planting.

How to Identify

Identify Chrozophora spp. by its grey, mealy foliage densely covered in star-shaped hairs, and its rhombic, wavy-edged leaves on a low, branching plant. Small yellowish male flowers and greenish female flowers occur together, followed by warty, three-lobed capsules. The silvery stellate hair covering and acrid milky sap mark it within the spurge family.

Appearance

Size & Dimensions

Height8" - 2'

Width/Spread8" - 1'8"

Colors

Flower Colors

Foliage Colors

Bloom Information

Bloom Period

~12 weeks

Summer Fall

Flowering occurs through the warm season, roughly June to September, with small flowers produced over a long period as the plant branches and grows. The inconspicuous flowers are followed by warty capsules that ripen and split to release seeds. Bloom continues until frost or drought ends growth.

Detailed Descriptions

Flower Description

yellowish to greenish

Foliage Description

grey-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 Range6.0 - 8.0(Neutral)

357912

Soil Types

sand loam rocky

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

tender

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Most Chrozophora spp. are not cultivated and grow as warm-season annuals or short-lived perennials on dry, open soils in full sun. The genus tolerates heat, poor soil, and drought and needs no irrigation once growing. Where C. tinctoria is grown for dye or study, it is sown in warm soil in a sunny, freely draining bed. The acrid sap can irritate skin and eyes on contact. Plants are frost-tender and die with the first hard freeze. None need feeding.

Pruning

No pruning applies to the annual or short-lived plants, which are spent after flowering and seeding. Self-sown seedlings can be removed where the genus behaves as a weed. Dead plants are cleared once they dry.