Optimizing Alfalfa Plant Harvesting: When and How to Cut for Maximum Yield and Quality

Alfalfa is often called the “Queen of Forages” for good reason. This versatile legume is highly productive fixing its own nitrogen from the atmosphere to fuel rapid growth. Alfalfa hay and silage provide an excellent source of protein energy, vitamins and minerals for livestock. However, to reap the full benefits of alfalfa, proper harvesting techniques are essential. In this comprehensive guide, we’ll explore optimal timing, methods and tips for harvesting your alfalfa to maximize yield, quality and stand life.

Why Timing Matters

Determining the optimal harvest window is one of the most important decisions an alfalfa grower makes all season. Cutting too early reduces tonnage and wastes potential growth. Harvesting late results in lower forage quality and stand decline over time. Agronomists recommend targeting the early bloom stage for first cut, when approximately 10% of plants have one open flower. This balances yield and quality.

As alfalfa matures, fiber levels increase while protein and digestibility decrease Fiber becomes lignified and indigestible by livestock Waiting too long drops feed value quickly. Using the growth stages of alfalfa as your guide, rather than calendar dates, results in the highest yields of nutritious forage.

Growth Stages of Alfalfa

• Vegetative: No buds present. Provides highest quality and protein content, but lower yields.

• Bud stage Swelling buds felt at stem tips Optimal for cutting pure alfalfa for dairy cattle,

• Early bloom: Less than 10% of plants with one open flower. Recommended for first cut of alfalfa-grass mixtures.

• Mid bloom: Up to 50% of stems flowering. Quality and yields are both decreasing as maturity advances.

• Full bloom: Over 50% in flower. Nutritive value drops sharply from here through seed-set.

Factors Influencing Harvest Timing

Along with growth stage, other considerations factor into optimal cutting time, including:

• Intended use – Dairy or beef cattle, replacement heifers, sheep or horses all have different nutritional needs. Know your target animal and harvest goals.

• Weather/drying time – Rainy or humid conditions slow curing. Wait until forecast is favorable for a 3-4 day dry-down period before cutting.

• Type of harvest – Silage can be cut a bit earlier than hay, which needs more field drying time to prevent spoilage.

• Stand age – Older stands decline more quickly when cut late. Stick to the 10% bloom guideline.

• Pest pressure – Cutting early helps control some insects and diseases. Scout fields and adjust timing accordingly.

• Fall harvests – Final cuts should occur 4+ weeks before first expected frost to allow sufficient regrowth before winter.

Harvest Methods

Once you’ve determined optimal timing, the next key decision is harvest method. Common options include:

Hay

Dried and baled at 80-90% dry matter. Lower cost, but very weather dependent. Requires 4-6 days of drying time in the field between cutting and baling. Significant leaf losses can occur during raking and baling if crop is too dry.

Baleage

Wilted to 50-60% dry matter, then baled and wrapped in plastic within 12-24 hours. Reduced drying time compared to dry hay. Minimizes leaf loss and weather risks. Requires specialized equipment.

Silage

Chopped and ensiled at 60-70% moisture. Fastest preservation of alfalfa quality. Can be harvested anytime. Needs a silo or bunker. Higher cost than hay or baleage.

Consider your climate, infrastructure, timeline, budget and livestock’s needs when deciding on harvest method.

Mowing Height Matters

Regardless of timing or harvest type, mowing height significantly impacts alfalfa stand persistence and longevity. Follow these guidelines:

• First cut – Leave 3-4 inches of stubble. Plants are shorter, and need more leaf area for regrowth.

• Summer cuts – Can mow closer to 2-3 inches once alfalfa is vigorously growing. Never below 2 inches.

• Last fall cut – Leave 4+ inches to protect crowns over winter.

Mowing too low damages crown buds and weakens stands. An extra inch maintains plant health and productivity season after season.

Allow Periodic Flowering

Managing alfalfa is a balancing act. While frequent harvesting maintains quality, the plant needs periodic flowering for root energy reserves. Failure to flower leads to stand decline. Here are two strategies:

• Rotational flowerings – Allow each field to flower every 2-3 cuttings before harvesting.

• Full flower stage – Take one cutting per season at nearly full flower before cutting again at the bud-bloom stage.

Either approach gives alfalfa time to bloom, while producing adequate yields and quality at other cuttings.

Optimal Cutting Intervals

Another key factor is allowing adequate recovery between cuttings for regrowth. Recommendations vary based on use, climate and plant stress:

• Dairy quality – Cut every 28-35 days

• Livestock feed – Cut every 35-42 days

• Arid climates – Cut every 42-50+ days

• Colder climates – Cut every 25-28 days

• Heat/drought stress – Widen interval to 6+ weeks

Adjust cutting schedule based on growing conditions, but never cut more than once every 3-4 weeks.

Top Tips for Productive Stands

Follow these best practices for optimizing alfalfa health, yield and quality:

• Scout fields regularly and control weeds, insects and diseases.

• Test soils every 2-3 years and apply needed fertilizers or soil amendments.

• Allow for periodic flowering cycles to maintain plant vigor.

• Never cut or graze shorter than 2 inches to avoid crown damage.

• Widen cutting intervals during stress periods or after insect/disease infestations.

• Harvest at early bloom stage for optimal yields and forage quality.

• Consider multi-cut versus single-cut harvest systems based on your climate and operation.

• Rotate harvests between fields to spread workload and avoid cutting any single field too frequently.

The Bottom Line

Properly managing alfalfa harvests requires understanding plant growth stages, field variability, climate patterns, curing times, harvest methods and livestock nutritional needs. While complex, mastering these concepts pays off with years of maximal production from healthy, persistent alfalfa stands. Work with your local extension agent or crop advisor to develop a tailored cutting schedule for each field based on best agronomic practices. With the right harvest techniques, alfalfa will keep thriving and delivering high-quality forage.