How to Grow Lucernes USA | Planting & Establishment

Growth Stages

Stage	BBCH	Notes
Sowing	0	RHS: propagate from seed sown in autumn. PFAF instead describes a spring sowing: pre-soak seed for 12 hours in warm water, then sow in situ; seed emerges within 7-14 days. The two sources genuinely differ on season -- both are given rather than silently picking one.
Establishment (deep taproot)	3	PFAF: develops a carrot-like taproot descending 6 metres or more into the soil, giving the plant genuine drought resilience once established; growth habit is described as a "clumper with limited spread" rather than a running or invasive plant.
Flowering	6	RHS: small purple flowers appear in summer, followed by flat, pea-like fruits. PFAF: under optimal conditions the plant reaches maturity within 60-90 days of sowing.
Harvest (leaves, seed, or sprouts)	8	PFAF: harvest young leaves and shoots through the growing season; alternatively, harvest mature seed to sprout indoors year-round -- ready to eat in as little as 4-6 days from soaking.

Quick Facts

Factor	Value
Sunlight	6-8 hours direct sun
Minimum survivable temp	-20C
Drainage	Well-drained (both sources); RHS: grows in most situations including poor, dry soil; PFAF: prefers rich, friable, loamy soil with loose topsoil and added lime, does not tolerate waterlogging.
Lifecycle	RHS: a herbaceous perennial legume with a deep tap-root, rated H7 (-20C or below) -- hardy anywhere in the UK. PFAF: perennial, fast-growing, a "clumper with limited spread" thanks to a taproot that can descend 6 metres or more into the soil.
Edible parts	leaves, sprouts, seeds

At a Glance

Harvest & Storage

When to pick: PFAF: pick young leaves and shoots before they toughen, eaten raw, cooked, or dried for later use. For sprouts specifically: soak seed 12 hours in warm water, then keep moist in a warm place -- ready to eat in about 4-6 days.

Storage

PFAF: dry leaves/shoots for longer storage; sprouted seed is best eaten fresh soon after sprouting, following safe sprouting hygiene practices given the risk of foodborne bacteria on raw sprouts.

Diseases

Bacterial wilt (unspecified, alfalfa)

RHS: may develop bacterial wilt; no causal organism named, so kept as a generic entry rather than a fabricated one.

Pests

Leafhoppers

Cicadellidae (various spp.)

RHS names leafhoppers generically among the pests affecting this species.

Alfalfa weevil

Hypera postica

RHS names alfalfa weevil among the pests affecting this species.

Spotted alfalfa aphid

Therioaphis maculata

RHS names spotted aphids among the pests affecting this species.

Lucerne (Alfalfa), Grown for its Sprouts and Leaves

Clover-like foliage

RHS: clover-like green foliage on a herbaceous perennial legume with a deep tap-root.

Small purple flowers in summer

RHS: small purple flowers appear in summer, followed by flat, pea-like fruits.

A genuinely hardy legume

RHS rates alfalfa H7, hardy anywhere in the UK even in severe winters -- it survives severe European continental climates too.

A distinctive curled seed pod

Following flowering, alfalfa forms a tightly coiled, spiral seed pod -- one of the plant's most distinctive identifying features.

Flower colour can vary

Alfalfa flowers can range from pale lilac to a very deep violet-purple depending on variety and growing conditions.

Grown as a field crop worldwide

PFAF: naturalised on waste ground across much of the world; fields like this one have long supplied both livestock forage and, increasingly, sprouting seed for human food.

An upright, fast-growing habit

PFAF: a fast-growing perennial reaching about 1m, described as a "clumper with limited spread" -- it doesn't run or spread invasively.

A deep taproot below ground

PFAF: below ground, a carrot-like taproot can descend 6 metres or more, giving the plant real drought resilience once established.

Leaves and shoots are the edible harvest

PFAF: young leaves and shoots are eaten raw or cooked, or dried for later use -- "very rich in vitamins, especially A, B and C."

References

1. Plants For A Future (PFAF) - Medicago sativa

   Habitat: waste ground, avoiding acid soils. Hardiness: USDA zones 4-11, UK zone 5, heat-tolerant zones 8-5. Soil: rich, friable, well-drained loamy soil with loose topsoil supplied with lime; mildly acid, neutral or basic, cannot grow in strongly acidic conditions. Sun: full sun, cannot grow in shade. Moisture: prefers well-drained, tolerates dry and moist, does not tolerate waterlogging. Size/habit: perennial to 1m, fast growth rate, taproot like a carrot descending 6m or more, "clumper with limited spread". Propagation: pre-soak seed 12 hours in warm water, then sow in spring in situ; emerges in 7-14 days, matures in 60-90 days under optimal conditions. Edible use: leaves/shoots raw or cooked or dried, very rich in vitamins A, B and C; sprouted seed (pre-soak 12 hours, then keep moist and warm, ready in 4-6 days); ground seed mixed with cereal flours for nutritionally improved bread. Medicinal use: antiscorbutic, aperient, diuretic, haemostatic, nutritive, stimulant, tonic; nutritive tonic to stimulate appetite; vitamin K aids blood clotting; used for asthma, diabetes, gastrointestinal disorders. Safety: contains saponin-like substances, large quantities may cause red blood cell breakdown; sprouts contain canavanine, ingestion can cause recurrence of systemic lupus erythematosus; avoid during pregnancy/lactation and for people with gout; may interfere with warfarin and corticosteroids. Also: a good bee plant and a food plant for many caterpillars. No specific pest/disease information given.

2. Royal Horticultural Society - Medicago sativa (lucerne)

   Hardiness H7 (-20C or below), survives severe European continental climates. Soil: chalk, clay, loam, sand; grows in most situations including poor, dry soil. Position: full sun to partial shade, east/north/south/west-facing. Exposure: exposed or sheltered. Size: height/spread 0.5-1m, 1-2 years to maturity. Moisture: moist but well-drained or well-drained. pH: acid, alkaline or neutral. Propagation: from seed sown in autumn. Pests: alfalfa weevil, leafhoppers, spotted aphids. Diseases: may develop bacterial wilt. Garden use: recommended for wildflower meadows and wildlife gardens; improves soil nutrient levels and reduces compaction. Description: deep tap-root, clover-like green foliage, small purple flowers in summer followed by flat pea-like fruits; traditionally used as animal feed and green crop.

2 independent sources are cited for this crop. Where they disagree - soil pH is the clearest case - every figure is preserved rather than averaged into false precision.