1 / 11

Medicago sativa

alfalfa

Fabaceae southwestern and central Asia

Attracts Pollinators Attracts Butterflies Drought Tolerant

SunFull Sun

WaterLow · drought-tolerant

HardinessZones 3–9

Overview

Medicago sativa is a deep-rooted perennial legume in the pea family, grown worldwide as a forage and hay crop and originally from southwestern Asia. It grows 1-3 feet (30-90 cm) tall in clumps of upright stems that regrow after cutting or grazing. The leaves are divided into three toothed leaflets, each 0.5-1.25 inches (1-3 cm) long, like a larger clover. From early summer into autumn it bears short clusters of small pea-like flowers, usually violet to purple, sometimes blue or yellow in related forms. The flowers give way to tightly coiled, spiraled seed pods that turn brown as they ripen. A taproot reaching 6-15 feet (2-4.5 m) deep lets the plant draw water and nutrients from far below the surface, so it withstands drought once established. Like other legumes, its roots fix nitrogen through bacterial nodules, enriching the soil. M. sativa grows on deep, well-drained, neutral to alkaline soils and is sensitive to waterlogging and acidity. Stands are productive for several years before they thin and need replanting.

Native Range

Medicago sativa originated in southwestern and central Asia and has been cultivated for thousands of years. It is now grown and naturalized across temperate regions worldwide, including much of North America, where it escapes from cultivation onto roadsides and field edges.

Suggested Uses

Medicago sativa is grown mainly as a hay, forage, and silage crop and as a cover crop that fixes nitrogen and improves soil. In gardens it is sometimes grown as a green manure, turned under to enrich beds. The flowers draw bees, and the sprouted seeds are eaten as a salad green.

How to Identify

Look for clover-like leaves of three toothed leaflets on upright, branching stems. The small pea-like flowers are usually violet to purple and held in short clusters. The ripe seed pods are coiled into tight spirals, unlike the straight pods of clovers and most other legumes.

Appearance

Size & Dimensions

Height1' - 3'

Width/Spread1' - 2'

Colors

Flower Colors

Foliage Colors

Fall Foliage Colors

Bloom Information

Bloom Period

~12 weeks

Summer Fall

Flowering runs from early summer into autumn, with repeated flushes after each cutting in hay fields. The violet to purple pea-like flowers open in short clusters and draw bees. Coiled seed pods follow and ripen brown a few weeks later.

Detailed Descriptions

Flower Description

violet to purple

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 Range6.5 - 8.0(Alkaline)

357912

Soil Types

loam sand clay

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

Grow Medicago sativa in full sun on deep, well-drained, neutral to alkaline soil; it does not tolerate acidity or standing water, both of which thin a stand. Its deep taproot draws moisture from well below the surface, so established plants withstand drought. Nitrogen-fixing root nodules supply most of the plant nitrogen, so no nitrogen feeding is needed, though phosphorus and potassium support yield. In hay use it is cut several times a season, regrowing from the crown each time. Stands stay productive for three to five years before they thin and are replanted. Crown and root rots, along with aphids and weevils, are the main pressures in wet or poorly drained ground.

Pruning

In garden settings no pruning is needed beyond cutting back spent growth. In forage use the plants are mown several times a year, cut a few inches above the crown so they regrow. Cutting at early flowering balances yield with regrowth.