1 / 2

Onobrychis spp.

sainfoins

Fabaceae

Europe, North Africa, and temperate Asia, centered on the Mediterranean and western Asia

Attracts Pollinators Attracts Butterflies Drought Tolerant

SunFull Sun

WaterLow · drought-tolerant

HardinessZones 3–8

Overview

Onobrychis is a genus of about 130 species of perennials, annuals, and spiny subshrubs in the pea family Fabaceae, native to Europe, North Africa, and temperate Asia, centered on the Mediterranean and western Asia. Most species carry pinnate leaves divided into many small, paired leaflets, on plants ranging from low cushions a few inches high to upright herbs 1-3 ft (30-90 cm) tall. Dense, cone-shaped spikes hold many small pea-like flowers, most often in pink to rose with deeper red veining, and white or pale yellow in some species. As legumes, the plants form root nodules with bacteria that fix nitrogen, and the flowers are rich in nectar that draws bees. O. viciifolia, common sainfoin, is grown as a forage crop and, unlike many legumes, does not cause bloat in grazing livestock. The genus grows in dry grassland, rocky slopes, and open scrub, often on chalky or limestone soils, and tolerates heat and drought. The single-seeded pods are flattened and often ridged or spiny. Most species are deciduous perennials hardy through USDA zones 3 to 8, though a few are annual or shrubby.

Native Range

Onobrychis is native to Europe, North Africa, and temperate Asia, with the greatest diversity around the Mediterranean and in western and central Asia. O. viciifolia has been carried beyond its range as a forage crop and is naturalized in parts of North America. Plants occur in dry grassland, rocky slopes, and limestone soils.

Suggested Uses

Onobrychis species are grown as forage and hay crops, as cover and green-manure plants that build soil nitrogen, and in wildflower and pollinator plantings for their nectar-rich pink spikes. Low, cushion-forming species are grown in rock gardens. On dry, alkaline ground the genus is used to stabilize slopes and feed bees.

How to Identify

Identify Onobrychis by pinnate leaves of many small paired leaflets and dense, cone- or spike-shaped clusters of pink pea-like flowers with darker veins. The flattened, often ridged or spiny single-seeded pods are a useful clue. Pink flower spikes over ferny legume foliage on dry, chalky ground point to sainfoin and its relatives.

Appearance

Size & Dimensions

Height4" - 3'

Width/Spread1' - 2'

Colors

Flower Colors

red

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~6 weeks

Spring Summer

Flowering occurs from late spring into summer, roughly May to July, with dense pink spikes opening from the base upward. Bloom lasts several weeks. Cut or grazed plants of O. viciifolia may flower again later in the season.

Detailed Descriptions

Flower Description

pink to rose

Foliage Description

green

Growing Conditions

Sun Requirements

SunFull Sun

Requires 6-10 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 Range6.5 - 8.0(Alkaline)

357912

Soil Types

loam sand chalk rocky

Drainagewell drained

Water & Climate

Water Needs

Low

Frost Tolerance

hardy

Time to Maturity

1-2 years

Drought Tolerance

Drought tolerant when established

Care & Maintenance

Care Guide

Onobrychis species grow in full sun in dry, well-drained soil, on neutral to alkaline ground with a pH near 6.5 to 8.0, including chalky and rocky sites. They tolerate heat and drought once established, drawing on deep taproots, and fix their own nitrogen, so they need no nitrogen feeding. The genus is cold-hardy through USDA zones 3 to 8 in the perennial species. Plants decline in waterlogged or acidic soil and are short-lived where drainage is poor. They are raised from seed, often inoculated with the right bacteria, as the taproot makes transplanting difficult. Established stands need little care beyond occasional cutting.

Pruning

Plants are cut or mown after the first flush of flowering to tidy growth and may produce a second, lighter bloom. Spent stems are cut back in late autumn or left to stand over winter. No detailed pruning is needed for this legume.