Stylosanthes spp.

pencilflower

Fabaceae Tropical and subtropical Americas

Attracts Pollinators Attracts Butterflies Drought Tolerant

Native to North America

SunFull Sun

WaterLow · drought-tolerant

HardinessZones 9–12

Overview

Stylosanthes spp. is a genus of about 25 to 50 species of herbs and subshrubs in the legume family (Fabaceae), native to tropical and subtropical regions of the Americas, with some species in Africa and Asia. Known as pencilflower or stylo, the plants grow 8-40 inches (20-100 cm) tall with a low, spreading to erect, often wiry and somewhat sticky habit and three-parted leaves. Small pea-like flowers in yellow to orange appear at the stem tips and in the leaf axils, each short-lived, followed by small hooked or jointed pods. Several species, including S. guianensis, S. hamata, and S. scabra, are grown widely as tropical pasture and cover-crop legumes for fixing nitrogen and persisting on poor, acidic soils. Stylosanthes spp. grows in full sun on well-drained sandy, gravelly, or lateritic soils and tolerates heat, drought, and low fertility. Some species are short-lived perennials, others behave as annuals. The genus is frost sensitive, suited to frost-free and warm climates, and can naturalize and spread where conditions favor it.

Native Range

Stylosanthes spp. is native to tropical and subtropical America, from the southern United States and the Caribbean through Mexico, Central America, and Brazil, with additional species in tropical Africa and Asia. It grows in savanna, open grassland, sandy and lateritic soils, and disturbed ground.

Suggested Uses

Stylosanthes spp. is used as a tropical forage and pasture legume, a cover crop, and a soil-improving, nitrogen-fixing plant on poor land. In gardens it suits sandy, low-fertility sites and warm-climate ground stabilization. Its flowers support pollinators in tropical and subtropical plantings.

How to Identify

Identify Stylosanthes spp. by its low, wiry, often sticky stems with three-parted leaves and small yellow to orange pea-like flowers borne at the tips and in the leaf axils. The flowers give way to small jointed or hooked pods with a curved beak. A spreading habit on poor sandy or lateritic soil in warm regions helps confirm the genus.

Appearance

Size & Dimensions

Height8" - 3'4"

Width/Spread1' - 3'

Colors

Flower Colors

yellow

orange

Foliage Colors

green

Bloom Information

Bloom Period

~14 weeks

Summer Fall

Flowering occurs through the warm growing season, mainly summer and into autumn in subtropical areas and much of the year in the tropics. Individual flowers last about a day, but bloom continues over a long period. Pods ripen quickly after flowering and shed seed freely.

Detailed Descriptions

Flower Description

yellow to orange

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 Range4.5 - 7.0(Acidic)

357912

Soil Types

sand rocky loam

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

tender

Time to Maturity

1 year

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Stylosanthes spp. grows in full sun on well-drained sandy, gravelly, or lateritic soils and tolerates heat, drought, and low fertility, fixing nitrogen as a legume. Water needs are low to medium, and plants establish on poor, acidic ground where many legumes fail. Soil pH from about 4.5 to 7.0 suits the genus. It is frost sensitive and suited to USDA zones 9-12 and frost-free tropical climates. Some species are short-lived and rely on self-sown seed to persist. Heavy, wet, or strongly alkaline soils reduce growth and survival.

Pruning

Pruning is minimal in garden use; in pasture the plants are grazed or mown to encourage branching and reseeding. Spent or frost-damaged growth is cut back as needed. Cutting too low can weaken short-lived stands.