How to Grow Alfalfa
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Alfalfa
Medicago sativa
herbAlfalfa is a deep-rooted, nitrogen-fixing legume widely cultivated for livestock feed and as a cover crop. This perennial plant produces small purple, blue, or yellow flowers and is valued for its high protein content and ability to improve soil fertility. It can be harvested multiple times per growing season and remains productive for 4-8 years.
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Example Alfalfa timeline · Pittsburgh, PA (Zone 6b)
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Plant Alfalfa
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Alfalfa
Around May 17≈ 30 days after planting
Sample dates for Pittsburgh, PA. Sign up to get exact Alfalfa dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 4-9; hardy perennial that tolerates cold winters and adapts to diverse climates
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Get my Alfalfa timeline →Growth Stages
Seed Germination
7-14 daysSeeds germinate and first true leaves emerge; seedlings are delicate with thin stems.
Keep soil consistently moist but not waterlogged. Protect seedlings from strong wind and heavy rain. Thin seedlings to proper spacing.
Vegetative Growth
3-4 weeksPlant develops multiple stems, compound trifoliate leaves, and establishes the deep taproot system. Growth accelerates in warm weather.
Maintain consistent moisture. Begin first cutting when plant is 6-8 inches tall and has reached early bud stage. Remove competing weeds.
Pre-flowering/Budding
1-2 weeksPlant reaches 12-18 inches tall; flower buds form in terminal clusters. This is the ideal harvest stage for forage quality.
Harvest at 10% bloom stage for maximum nutrition. Allow some plants to flower if growing for seed or wildlife benefit.
Flowering
2-3 weeksPurple, blue, or occasionally yellow flowers bloom in dense clusters. Plant is at maximum biomass but decreasing nutritional quality.
For forage, avoid harvesting at full bloom as feed quality declines. Allow flowering if supporting pollinators or saving seed.
Regrowth and Dormancy
4-6 weeks per cycle; winter dormancy 4-6 monthsAfter cutting, plant rapidly regrows from crown buds. In late fall, growth slows; plant enters winter dormancy.
Allow at least 4-6 weeks between final cutting and hard frost to permit dormancy preparation. Do not harvest after mid-September in cold climates.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Early harvest (before pest emergence), parasitic wasps, neem oil, insecticidal soap on seedlings
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Encourage natural predators (ladybugs, lacewings), insecticidal soap, neem oil, resistant varieties
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Timely harvest, Bacillus thuringiensis (Bt), encourage native predators
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Early cutting, neem oil, encouraging natural predators, removal of nearby grass debris
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Improve drainage, rotate crops, avoid overwatering, ensure adequate soil aeration
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Crop rotation (3-5 years away from alfalfa), select resistant varieties, avoid infected soil
Uses
Sprouting and Nutrition
CulinaryAlfalfa sprouts are nutrient-dense additions to salads, sandwiches, and smoothies, providing vitamins K, C, A, and minerals. Raw sprouts contain enzymes that aid digestion. [source]
Herbal Supplement and Wellness
MedicinalTraditionally used in herbal medicine to support joint health, aid digestion, and provide chlorophyll. Modern studies investigate its role in cholesterol management and menopausal symptom relief. [source]
Nitrogen Fixation and Soil Improvement
AgriculturalAs a legume, alfalfa forms symbiotic relationships with Rhizobium bacteria in the soil, fixing atmospheric nitrogen and enriching soil for subsequent crops. This reduces the need for synthetic fertilizers. [source]
Pollinator and Beneficial Insect Support
WildlifeAlfalfa flowers attract bees, butterflies, and native pollinators. The plant provides habitat and food for beneficial insects and small mammals. [source]
Animal Feed and Livestock Nutrition
HouseholdAlfalfa hay and fresh forage are premium livestock feed, providing high protein, vitamins, and minerals. Widely used for horses, cattle, rabbits, and poultry. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
Harvest when plants reach early bud stage (10% bloom) at 6-10 weeks from emergence, cutting 2-3 inches above the crown. This timing maximizes nutritional value for livestock feed. Allow regrowth of 4-6 weeks between cuts. In the first year, take only 1-2 cuttings; established stands can yield 3-5 cuts per season. Stop harvesting 4-6 weeks before the first hard frost to allow plant dormancy preparation. For seed production, allow one cutting to flower fully and dry on plant before threshing.
Fun Facts
- 🌱 Alfalfa has an exceptionally deep taproot system that can extend 10-20 feet into the soil, allowing it to access water and nutrients unavailable to shallow-rooted plants and making it extraordinarily drought-tolerant once established.
- 🌱 A single alfalfa plant can live and produce for 4-8 years or longer, making it more cost-effective than annual crops and providing long-term soil improvement.
- 🌱 Alfalfa is the third-largest U.S. crop by acreage (after corn and soybeans) and is primarily grown as a forage crop; the United States produces over 30 million tons of alfalfa hay annually.
Gardening Terms
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