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Alfalfa Hay for Horses: The Truth about Feeding Alfalfa Hay

Last updated: August 16, 2023

By: Miles HenryFact Checked

As someone who interacts with a lot of horse owners, I’ve noticed that many feed their horses alfalfa daily. I often questioned this, especially when considering horses that don’t need the extra calories. So, should you feed your horse alfalfa? The decision isn’t black and white. It hinges on factors like the horse’s activity level, overall health, and the balance of their diet.

Alfalfa hay can be a boon for horses that have trouble maintaining weight or those engaged in intensive training. However, it might not be ideal for rapidly growing young horses or those with liver or kidney conditions. And for horses that don’t need the added calories or protein? Alfalfa might be more of a luxury than a necessity.

Given the maze of conflicting information online about alfalfa, I felt compelled to offer a reliable resource. In this article, we’ll explore the specifics of feeding alfalfa, pinpoint which horses benefit most, and address concerns like potential health risks such as ulcers or colic. Let’s dive in.

What is Alfalfa Hay?

Alfalfa hay isn’t just any ordinary grass; it’s a powerhouse plant with deep historical roots. Have you ever wondered about its origins or how it’s different from standard grass hay? Let’s dig in.

Brief History and Origin

Alfalfa is like the great-great-grandparent of many forage crops, having been around for thousands of years. Originating from South Central Asia, it made its way to the Mediterranean regions, becoming a popular feed for horses in ancient Greek and Roman civilizations. These ancient folks knew their stuff because, fast forward to today, alfalfa is now grown and recognized globally as a high-quality fodder.

Differences Between Alfalfa Hay and Other Common Types of Hay

  1. Appearance: While alfalfa hay has a deep green hue with little leafy clusters and thin stems, other hays, like Timothy or Bermuda, might appear lighter with thicker stems.
  2. Nutritional Content: Alfalfa stands out for its rich protein content, making it the muscle-building supplement of the hay world. In comparison, grass hays like timothy are usually lower in protein but higher in fiber, which is great for digestion.
  3. Taste and Texture: Ask a horse (if they could talk), and they might tell you that alfalfa is the tasty treat they’ve been waiting for. Its soft, leafy texture and slightly sweet taste make it a favorite. Meanwhile, other hays might be coarser with a milder taste.
  4. Use and Purpose: Because of its nutritional punch, alfalfa is often the go-to for equines needing weight gain or extra energy, like performance horses. On the other hand, grass hays, due to their fiber richness, are a staple for good digestion and are often fed to leisure horses or those with lower energy needs.

In essence, while alfalfa is like the protein shake of the hay family, other types are more like a balanced meal, each serving its unique purpose. Next time you pick up a bale or admire a field of growing hay, you’ll know a bit more about what’s what!

Nutritional Profile of Alfalfa Hay

Alfalfa hay, often referred to as the “Queen of Forages,” is more than just a bunch of green leaves. It’s a nutritional goldmine! Understanding its content can help horse owners make informed decisions about their horse’s diet. So, what makes alfalfa hay the go-to choice for many?


  1. Protein: Alfalfa hay is a high-protein forage, often boasting levels between 15% to 20%. This protein content supports muscle growth, making it particularly valuable for young, growing horses and high-performance equines.
  2. Fiber: This hay isn’t just about protein. Its fiber content aids in digestion, ensuring that our equine friends maintain a healthy gut. It provides a good balance of both soluble and insoluble fibers.
  3. Carbohydrates: While not as carbohydrate-dense as grains, alfalfa does contain a reasonable amount of carbs, primarily in the form of naturally occurring sugars and starches. These carbs are an energy source, helping to fuel a horse’s daily activities.

Essential Minerals:

  1. Calcium: A standout among the minerals in alfalfa is calcium. It’s abundant and supports strong bones and teeth. This mineral’s high levels also make alfalfa an excellent choice for lactating mares.
  2. Phosphorus: While present in lower amounts compared to calcium, phosphorus works in tandem with it to support skeletal health.
  3. Magnesium: Important for muscle function and metabolic processes, magnesium is another mineral generously found in alfalfa.


  1. Vitamin A: Essential for vision, reproduction, and immune system health, alfalfa hay is a natural source of this vital vitamin.
  2. Vitamin D: Known as the ‘sunshine vitamin’, it aids in calcium absorption, ensuring strong bones.

Importance of Nutrient Balance for Equine Health:

Feeding our horses isn’t just about filling their bellies. It’s about providing them with the right balance of nutrients. While alfalfa hay is nutritionally dense, it’s essential to ensure that it complements the overall diet of the horse.

Too much of a good thing can lead to imbalances. For example, an excess calcium intake from alfalfa needs to be balanced with phosphorus from other dietary sources. A well-rounded diet ensures optimal health, performance, and longevity for our equine companions.

When it comes to packing a nutritional punch, alfalfa hay is hard to beat. But like any dietary choice, it’s all about balance and understanding the needs of each individual horse.

Benefits of Feeding Alfalfa Hay to Horses

When we think of alfalfa hay, we might just see it as another component of a horse’s diet. But delve a bit deeper, and it becomes evident that this isn’t just any forage. It’s packed with benefits that cater to the various needs of our equine companions. So why do many horse enthusiasts and professionals swear by it?

1. High-Quality Protein for Muscle Development:

  • Muscle isn’t built by exercise alone. Protein plays a pivotal role, and alfalfa hay provides it in abundance. The high-quality protein in alfalfa aids in the repair and growth of muscles, making it an excellent choice for horses that undergo rigorous training or are in their growth phase.

2. Digestible Energy Source:

  • Everyone needs energy, and horses are no exception. The carbohydrates present in alfalfa hay, predominantly in the form of natural sugars and starches, provide a steady and digestible energy source. This ensures that our four-legged friends are fueled for their daily activities, be it a leisurely trot or a high-intensity race.

3. Beneficial for Specific Groups:

  • Lactating Mares: Producing milk is no small feat, and lactating mares have heightened nutritional demands. Alfalfa hay, with its rich protein and calcium content, supports milk production, ensuring the health of both the mare and her foal.
  • Young Growing Horses: Just like human toddlers, young horses have rapid growth phases. Alfalfa hay provides the essential nutrients needed for their proper development.
  • Performance Horses: Athletes, whether human or horse, require a diet that supports their activity level. For performance horses, alfalfa hay offers the nutritional boost they need to shine in their respective sports.

4. Bone Health Benefits Due to Calcium Content:

  • Bones are the framework of any body, and keeping them strong is crucial. The high calcium content in alfalfa hay promotes robust bone development and maintenance. It’s not just about strength, though. Calcium also plays a role in various physiological processes, ensuring that the horse’s body functions seamlessly.

When used correctly, alfalfa hay isn’t just food. It’s a strategic tool to ensure our horses are at the peak of their health and vitality. By understanding its benefits, horse owners can harness the full potential of this remarkable forage.

Picture of a horse eating alfalfa hay.

Horses that benefit from eating alfalfa.

Alfalfa is a nutrient-dense forage containing crude proteins, calcium, and high-quality fiber without much sugar. These qualities make it excellent hay to feed underweight horses. Also, horses that are insulin resistant can’t eat many grass hays because of their high sugar content, so alfalfa is a good alternative for them.

Horses that work hard benefit from eating alfalfa because it’s a good protein source and replaces lost calories. For example, every racehorse I’m aware of has its diet supplemented with alfalfa. Alfalfa aids horses with muscle weakness and reduces tying up caused by their high protein needs.

Foals and yearlings that aren’t getting enough protein either because their mother isn’t producing it in her milk or don’t suck should be fed alfalfa. However, feeding alfalfa to young horses is tricky because too much protein causes bone growth abnormalities. I suggest consulting your vet before feeding alfalfa to a young horse.

Here is a chart of the nutritional values of alfalfa hay as a percentage of dry matter:

Digestible Energy2.0 Mcal/kg
Vitamin A (IU)9,500
Vitamin E (IU)3.00

Please note that these values will vary depending on the growing conditions of the hay. It’s also important to note that the nutritional content of hay can change over time, so it’s best to use these values as a general guide.

Picture of bermudagrass hay next to alfalfa hay
Alfalfa next to bermudagrass hay.

Potential Concerns About Feeding Alfalfa Hay to Horses

Alfalfa hay, while packed with benefits, isn’t without its controversies. As with any food source, it’s all about moderation and understanding. Let’s delve into some common concerns and misconceptions surrounding this nutrient-rich forage.

  1. Risks of Excessive Protein:
    • Concern: Overfeeding protein can lead to excessive urination, making horses thirsty and possibly stressing their kidneys over time.
    • Reality: While it’s true that horses excrete excess protein through urine, healthy kidneys are designed to handle this. Problems arise only when there’s an existing kidney condition. However, it’s always a good idea to ensure a balanced diet and consult with a vet about appropriate protein levels.
  2. Mineral Imbalances: Calcium to Phosphorus Ratio:
    • Concern: Alfalfa is rich in calcium but not as high in phosphorus, leading some to worry about an imbalance affecting bone health.
    • Reality: While alfalfa does have more calcium than phosphorus, the imbalance can be corrected by ensuring a varied diet that includes grains or other hays, which are typically higher in phosphorus.
  3. Possibility of Weight Gain if Not Managed:
    • Concern: The rich nutrient content in alfalfa can lead to weight gain if fed excessively.
    • Reality: Like any food, moderation is key. Monitoring the horse’s weight and adjusting feed accordingly ensures that they reap the benefits of alfalfa without the unwanted weight gain.
  4. Alfalfa and Laminitis Concerns:
    • Concern: Some believe that alfalfa can trigger laminitis, a painful condition of the hooves.
    • Reality: While high carbohydrate levels in any feed can be a concern for laminitis-prone horses, it’s not alfalfa-specific. Properly cured alfalfa doesn’t pose a higher risk than other hays. Always keep an eye on at-risk horses and feed appropriately.
  5. The Truth About “Hot” Behavior in Horses from Alfalfa:
    • Concern: A common myth is that alfalfa makes horses “hot,” or overly energetic and hard to manage.
    • Reality: While alfalfa is energy-dense, it doesn’t inherently make horses hyperactive. Behavioral changes are likely multifactorial. Factors such as training, environment, and overall diet play a role. It’s always essential to look at the bigger picture.

Knowledge is the antidote to misconceptions. By understanding alfalfa’s true nature and potential concerns, horse owners can feed with confidence, ensuring their horses thrive.

How to Properly Introduce Alfalfa Hay into a Horse’s Diet

Imagine diving into a rich, three-course meal after subsisting on plain bread for a week. Your stomach would protest, right? Similarly, introducing any new food, including alfalfa hay, into a horse’s diet needs a measured approach. Let’s explore how to do it right.

  1. Gradual Introduction:
    • Start Slow: If your horse has been primarily on grass hay, don’t immediately switch over to full rations of alfalfa. Begin by substituting a small portion of their regular hay with alfalfa. Over 7-10 days, you can gradually increase the alfalfa proportion until the desired mix is achieved.
    • Mix and Match: Mixing alfalfa with their current hay can make the transition smoother and more palatable.
  2. Monitoring for Signs of Digestive Upset:
    • Be Observant: Watch out for symptoms like loose stools, bloating, or signs of colic. These might indicate that the horse isn’t adjusting well to the new feed.
    • Stay Hydrated: With its richer nutrient profile, alfalfa may make horses drink more water. Ensure they always have access to fresh water and monitor their drinking habits.
  3. Importance of Consistent Quality:
    • Know Your Source: All alfalfa isn’t created equal. Ensure you’re sourcing from a reputable supplier who provides consistent quality.
    • Look Before You Feed: Always inspect the hay for mold, dust, or foreign objects. Bad-quality hay can lead to respiratory and digestive issues.
  4. Adjusting Portions Based on Age, Activity Level, and Specific Needs:
    • Age Factor: Young, growing horses might benefit from more alfalfa due to its high protein content, while older horses might need it in moderation, depending on their health.
    • Activity Level: Performance horses or those with higher energy expenditures might need larger portions, while sedentary horses might need less.
    • Specific Needs: Lactating mares or underweight horses might require more alfalfa for its nutritional density. However, always consult with a vet or equine nutritionist to tailor the diet to the horse’s unique needs.

Remember, like humans, each horse is an individual with its own dietary preferences and needs. Introducing alfalfa hay is not just about the hay itself but also about understanding and catering to the unique characteristics of each horse.

Mixing Alfalfa with Other Hays

Diversifying a horse’s diet with a mix of hays can be likened to us enjoying a well-balanced meal with varied ingredients. By blending alfalfa with other hays, you provide a spectrum of nutrients while capitalizing on the strengths of each type. Let’s explore why and how to do this effectively.

  1. The Benefits of a Balanced Diet:
    • Nutritional Harmony: Each type of hay brings its own nutrient profile to the table. By mixing, you can achieve a more balanced ratio of proteins, fibers, vitamins, and minerals.
    • Digestive Health: Different hays have various fiber structures. This diversity can aid digestion and ensure smooth gut functioning.
    • Palatability: Some horses might prefer a mix over a single type of hay, leading to better feed consumption and less waste.
  2. Common Mixes: Alfalfa with Timothy or Grass Hay:
    • Alfalfa & Timothy: This is a popular mix in the equine world. While alfalfa is protein and calcium-rich, timothy hay offers a good balance of fiber and is generally lower in protein and calcium. Together, they create a well-rounded feed option.
    • Alfalfa & Grass Hay: General grass hays can be lower in calories and protein compared to alfalfa. Mixing them can help balance the rich nutrient content of alfalfa, making it suitable for horses that don’t need a highly calorie-dense diet.
  3. Proportion Considerations:
    • Purpose of the Mix: If you’re aiming to provide a high-protein diet for, say, a lactating mare or a young horse, the proportion of alfalfa might be higher. On the other hand, for a mature horse with moderate activity, a 50-50 mix or even less alfalfa could be ideal.
    • Monitor and Adjust: Keep a close eye on the horse’s condition and weight. If the horse seems to be gaining too much weight or showing signs of digestive upset, you might need to adjust the proportions.
    • Consultation: Always consider seeking advice from an equine nutritionist or veterinarian. They can provide guidance tailored to your horse’s specific needs and conditions.

While alfalfa is a nutritional powerhouse on its own, mixing it with other hays can provide a balanced and tasty meal for our equine companions. Like a chef perfecting a recipe, finding the right mix will depend on the specific needs and preferences of each individual horse.

Alfalfa May Not Be the Best Choice for Your Horse

There are some downsides to feeding some horses alfalfa hay. You need to know the risks before deciding whether or not it’s safe for your horse to eat this type of forage. While alfalfa hay can be a great source of nutrition for working horses, it may not be suitable for non-working horses due to its high-calorie content.

Overfeeding alfalfa can cause weight gain and other health issues. For example, you shouldn’t feed horses with liver or kidney problems high protein diets, including alfalfa. It is also not a good idea to feed endurance horses too much alfalfa.

Alfalfa provides high protein levels, which creates heat when it metabolizes, which isn’t good for endurance horses. The heat requires horses to sweat more, drink more, and urinate. To combat these effects, only feed alfalfa as a supplement with grass hay.

Also, horses diagnosed with HYPP (a genetic muscle disease prevalent in some quarter-horse pedigrees) should not be fed alfalfa or only in small amounts. The high concentration of potassium in alfalfa can cause the symptoms of the disease to worsen. Horses who are allergic to ragweed should avoid alfalfa hay because they may have an allergic reaction.

Alfalfa hay is expensive.

Currently, we pay about twenty dollars for a two-wire bale of alfalfa hay. That’s high when you consider a bale of Alicia hay sells for eight dollars. However, demand must be good even though I recently read that its popularity has declined because of its high price tag.

Among my family and friends, alfalfa’s skyrocketing prices have not deterred them from continuing to feed it. People pay such a high price because no other forage provides all the benefits you get in alfalfa.

Below is a YouTube video discussing the benefits of alfalfa hay.

YouTube video

Feeding Alfalfa Hay for Optimal Equine Health

Your decision to feed alfalfa to your horse should be based on its need. To determine what to feed your horses, you should calculate how much digestible energy, protein, and calcium it needs. Most lightly worked horses meet their daily nutritional requirement by grazing throughout the day. But what if a horse eats the same amount of alfalfa as grass per day?

As I stated earlier, a 1,000-pound horse eats about two percent of its body weight in grass or grass hay. If a horse eats two percent of its body weight in alfalfa, the excessive calories are converted to fat. The abundant protein converts to ammonia and, along with the excess calcium, passes through the kidneys as urine.

A horse continuing on a diet of only alfalfa hay would become obese and produce a lot of ammonia-smelling urine. The best method is to feed alfalfa as a supplement with grass hay. Grass hay typically can’t meet the increased demand for horses’ energy when they are worked; this is especially true for racehorses, sport horses, and endurance horses.

For example, an average-sized horse in light work needs approximately 18.4 mega calories daily of digestible energy, 1.4 pounds of crude proteins, and 27 grams of calcium. In 17.5 pounds of grass, hay provides 15.75 mega calories of digestible energy, 14 pounds of crude protein, and 39 grams of calcium.

These levels are a bit low for its daily needs of digestible energy, and to hit its daily requirements; you need to supplement its diet with grain, more grass hay, or alfalfa. Now let’s look at the nutritional values for the same amount of alfalfa hay.

In 17.5 pounds of alfalfa, you get 19.25 mega calories of digestible energy, 3.62 pounds of crude protein, and .24 pounds of calcium. Alfalfa clearly provides more than the daily recommended amounts for all three. So it would be best for your horse, in this situation, to cut back on the alfalfa and substitute grass hay.

Picture of a 44 lb. bale of hay.


In the world of equine care, the age-old adage “knowledge is power” rings especially true. Making an informed decision about what we feed our horses can profoundly affect their health, longevity, and quality of life.

Every bale of hay, every handful of grains, tells a story of nutrition, care, and the desire to offer our equine companions the very best. Alfalfa hay, with its rich nutritional profile, has stood out as a favored choice for many.

Yet, as we’ve seen, its introduction and consistent use in a horse’s diet require a blend of research, observation, and intuition. It’s not just about the hay itself but about the unique individual who’s consuming it.

Every horse has its own set of needs, preferences, and quirks. Recognizing and respecting these nuances can make all the difference in ensuring they lead a healthy and fulfilling life. And while knowledge provides a foundation, it’s the keen observation that offers the truest insights.

The gleam in a horse’s eye, the shine of its coat, its energy levels, and even the smallest changes in behavior can speak volumes. As caretakers, our responsibility doesn’t end once the feed is in the trough. It’s a continuous journey of watching, learning, and adapting.

To every horse owner and caretaker reading this, let’s pledge to remain ever-vigilant and always strive for the well-being of our majestic companions. May our decisions be informed, our actions kind, and our observations sharp, ensuring that the horses under our care thrive in every gallop and trot.


Does alfalfa make horses hot?

Alfalfa can make a horse hot if improperly fed. Alfalfa is high in protein and digestible energy (the net amount of energy an animal gets from its food), so you should feed it to horses that need the extra energy.

Does alfalfa cause colic in horses?

Alfalfa is rich and can cause colic in some horses. It is always a best practice to gradually change horses’ diet and introduce alfalfa by feeding it with grass hay.

Can alfalfa cause diarrhea in horses?

Alfalfa hay can cause diarrhea in a horse that overeats it because it is rich and full of nutrients. Overeating alfalfa can also cause a horse to have excess gas, develop laminitis, and founder.