How to Grow Magna II Alfalfa
Magna II Alfalfa
Medicago sativa 'Magna II'
herbMagna II is a winter-hardy, dormant alfalfa cultivar bred for cold climates and forage production. It is known for exceptional winter survival, disease resistance, and consistent yields across diverse growing conditions. This perennial legume fixes nitrogen and is widely used as livestock feed and soil improvement.
When should you plant Magna II Alfalfa in your zone?
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Example Magna II Alfalfa timeline · Pittsburgh, PA (Zone 6b)
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Plant Magna II 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 Magna II Alfalfa
Late summer into fallBefore the first fall frost (≈ Nov 8)
Sample dates for Pittsburgh, PA. Sign up to get exact Magna II Alfalfa dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Thrives in zones 2-8; exceptional winter hardiness makes it ideal for northern regions
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Get my Magna II Alfalfa timeline →Growth Stages
Germination & Seedling
7-14 daysTiny seedlings emerge with cotyledons and first true leaves; very vulnerable to competition and environmental stress
Keep seedbed moist but not waterlogged; avoid heavy foot traffic; apply herbicides carefully if needed for weed control; thin if overcrowded
Establishment
4-8 weeksPlant develops root system and first compound leaves; slow above-ground growth while energy is invested in taproot development
Avoid early grazing or cutting to allow root establishment; maintain consistent moisture; monitor for seedling diseases; suppress competitive weeds
Vegetative Growth
6-12 weeks per cutting cyclePlant develops multiple stems, compound leaves, and increasingly robust crown; visible leafy shoots from the root crown
First cutting can occur at bud to early bloom stage; allow regrowth between cuts; begin nitrogen monitoring (should be minimal due to N-fixation); scout for pests and diseases
Flowering & Seed Production
2-4 weeks per growth cyclePurple to violet flowers appear in dense clusters along stems; this stage signals peak nutritional value in forage
Cutting at early to mid-bloom maximizes nutritional quality for livestock; allow some flowering to maintain plant vigor and encourage regrowth; avoid cutting when soil is too wet
Dormancy & Winter
4-6 months (varies by zone)Plant slows growth significantly; above-ground portions may die back in cold regions; energy is stored in roots and crown
Magna II's winter hardiness is a major advantage; provide protection by avoiding late-season cutting that prevents carbohydrate recovery; avoid heavy grazing in fall; mulch can help in extreme cold zones
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Early spring scouting; cutting before weevil pupation; insecticides (pyrethrins, spinosad) if thresholds exceeded; encourage parasitic wasps
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Timely cutting removes infested leaves; resistant varieties like Magna II help; avoid over-fertilization
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and
(Noctuidae family)
Monitor and treat with approved insecticides if populations warrant; cultural practices like proper cutting timing reduce damage
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Scout regularly; natural enemies (ladybugs, lacewings) provide control; cutting removes heavy infestations
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More common in hot, dry conditions; adequate irrigation helps; miticides only if severe
Uses
Livestock Feed & Forage
CulinaryMagna II is primarily grown as high-protein forage for dairy cattle, beef cattle, horses, and other ruminants. Its superior digestibility and consistent palatability make it a cornerstone of commercial and farm feed operations. [source]
Phytonutrient Content & Traditional Use
MedicinalAlfalfa has been used traditionally in herbal medicine and contains saponins, flavonoids, and other bioactive compounds. Modern research investigates its potential effects on cholesterol and general wellness. [source]
Soil Improvement & Nitrogen Fixation
HouseholdAs a legume, Magna II fixes atmospheric nitrogen through symbiotic bacteria (Sinorhizobium meliloti), enriching soil for subsequent crops. This reduces the need for synthetic nitrogen fertilizers in crop rotations. [source]
Pollinator & Wildlife Support
WildlifeAlfalfa flowers attract and support bees, butterflies, and other pollinators, providing nectar and pollen resources. The plant also serves as food for various herbivores and supports diverse farm ecosystems. [source]
Cover Crop & Erosion Control
CraftMagna II's deep taproot system helps prevent soil erosion and improves soil structure. It is widely used in conservation programs and sustainable farming to restore degraded soils. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
First cutting typically occurs 60-90 days after planting. Harvest at early to mid-bloom stage (10% flowers) for optimal nutritional quality in hay. Use a sickle bar mower or rotary cutter. Avoid cutting when soil is too wet to prevent soil compaction and crown damage. Allow 4-6 weeks between cuts for regrowth and crown recovery. In cold climates, cease cutting 4-6 weeks before first frost to allow carbohydrate storage for winter survival. Magna II typically yields 3-5 cuttings per season in favorable conditions, or 2-3 in northern zones.
Fun Facts
- 🌱 Magna II was specifically bred for northern regions and can survive winter temperatures well below -30°F, making it one of the hardiest alfalfa cultivars available.
- 🌱 Alfalfa's deep taproot can extend 10-20 feet into the soil, allowing it to access water and nutrients unavailable to shallow-rooted plants, making it exceptionally drought-tolerant once established.
- 🌱 A single alfalfa plant can produce 300+ seeds per flower head, and a mature plant may bloom and regrow 3-5 times per season, providing multiple harvests and continuous forage throughout the growing season.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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