Alfalfa hay — dried forage from the Medicago sativa plant — is the most widely traded forage crop in the world. As a legume rather than a grass, it fixes atmospheric nitrogen through its root system, producing protein concentrations that no common grass hay comes close to matching. One ton of quality alfalfa contains as much protein as two-thirds of a ton of soybean meal and as much digestible energy as 25 bushels of corn.
That density is why it is called the “king of forages” — and why it remains the benchmark forage for dairy, beef, horse, and sheep operations globally.
Nutritional Profile at a Glance
| Nutrient | Typical Range |
|---|---|
| Crude Protein (CP) | 15–22% |
| ADF | 27–35% |
| NDF | 34–44% |
| Calcium | 1.2–1.8% |
| Phosphorus | 0.2–0.3% |
| TDN | 56–65% |
Quality varies significantly by cutting timing and maturity. Early-cut alfalfa — harvested before or at early bloom — delivers the highest protein and lowest fiber. Later cuttings are stemmer, higher in ADF, and less digestible.
What Makes Alfalfa Nutritionally Distinct
Protein. At 15–22% crude protein, alfalfa reliably meets the requirements of high-producing dairy cows (16–17% CP), lactating ewes, and growing animals without supplemental protein concentrate. Most grass hays run 10–14% CP and fall short for demanding animal classes.
Minerals. Alfalfa accumulates calcium, magnesium, potassium, zinc, iron, and manganese at concentrations that exceed grass forages. Its calcium content is particularly significant for lactating animals and growing stock. The calcium-to-phosphorus ratio of approximately 5–6:1 reduces or eliminates the need for supplemental calcium in most ruminant diets — a meaningful cost offset in commercial operations.
Vitamins. Leafy green alfalfa is naturally high in beta-carotene (vitamin A precursor), vitamin E, and vitamins D and K from sun curing. Vitamin A deficiency is the most common micronutrient deficiency in beef cows; good-quality alfalfa addresses it without supplementation. Vitamin content declines during storage, so recently harvested hay delivers more than older stocks.
Bioactive compounds. Alfalfa contains saponins, flavonoids, and polysaccharides that support gut health and act as natural rumen buffers, helping maintain rumen pH above 6.2 — the threshold below which fiber digestion is impaired. Diets with alfalfa as the primary forage generally do not require added buffers.
Key Benefits in Commercial Feeding Programs
Reduced supplementation costs. Because alfalfa simultaneously contributes protein, energy, calcium, magnesium, and vitamins, it replaces multiple purchased inputs. The cost-per-unit-of-nutrition comparison with supplemented grass hay typically favors alfalfa when protein prices are elevated.
High palatability. Animals actively prefer alfalfa over most grass hays, supporting voluntary intake — a direct advantage for dairy cows and finishing animals where maximum consumption drives production outcomes.
Broad species applicability. Cattle, horses, sheep, goats, and rabbits all consume alfalfa effectively, with appropriate adjustments to inclusion rate by species and production stage.
Limitations to Know
Bloat risk. Alfalfa can cause frothy bloat in ruminants, particularly when introduced abruptly or when animals are hungry before access. Properly cured dry hay carries lower risk than fresh or ensiled alfalfa, but gradual introduction is always recommended.
Calcium-phosphorus imbalance. The high Ca:P ratio requires phosphorus balancing in rations for beef steers and dry cows. It is ideal for lactating and growing animals but needs management in others.
Not the right sole forage for all horses. Alfalfa provides less crude fiber than grass hay and is very energy and protein dense. Most healthy adult horses at maintenance do better on mixed hay with alfalfa as a supplement rather than the primary forage.
Interested in sourcing bulk Medicago alfalfa hay? Contact our team to discuss specifications and supply availability.