You'll never forget that first real winter as a horse owner. As the temperatures start to drop, your anxiety will start to rise. You stand in the feed store aisles, staring at the different bales and feed options, completely overwhelmed. If you're lucky, someone who was once in your shoes will notice the panic in your eyes, lean over, and say, "You're overthinking it. Just keep his furnace burning."
When I first heard that phrase—"keep his furnace burning"— it stuck with me. It’s the perfect way to think about feeding horses in winter.
When the snow flies and the wind howls, feeding isn't just about calories; it’s about generating internal warmth. And one of the biggest debates you'll hear in any barn aisle (or social media) is about the best hay for horses in winter. Specifically: Does feeding alfalfa actually keep them warmer than regular grass hay?
It’s a question I hear all the time from new horse owners in our community. You want to do right by your new four-legged friend, but the advice can be conflicting. So, let’s settle this once and for all with a little science, a little experience, and a whole lot of practical advice.
True or False: Alfalfa helps keep horses warmer during digestion than grass hay?
The short answer is True. But like everything with horses, the "why" and "how" are just as important as the answer itself. Let’s dive in.
Understanding the Equine Furnace
Before we get into the nitty-gritty of feeding horses alfalfa in winter, we need to understand how horses stay warm. Unlike us, they don’t just rely on external layers (though a good blanket can help in some circumstances). They have an incredible internal heating system.
Horses are hindgut fermenters. This is a fancy way of saying that the majority of their digestion happens in the large intestine (the hindgut), where billions of microbes break down fiber. This fermentation process is fascinating—and vital. As those microbes work hard to break down the hay you feed, they produce heat as a byproduct. This is often called the “heat of digestion.” The hindgut is a crucial part of the horse's digestive tract, and microbial fermentation here not only aids digestion but also generates internal heat that helps horses stay warm in winter.
Think of your horse’s hindgut like a wood-burning stove.
Grain is like paper or kindling. It burns hot and fast, giving a quick burst of energy, but fades quickly. It doesn’t provide sustained warmth. Maintaining adequate forage intake is essential for regulating your horse's body temperature, as the slow fermentation of fiber provides a steady source of heat.
Hay (Forage) is like a big, dense oak log. It burns slowly and steadily, radiating heat for hours.
Consistent forage intake is key to keeping that internal fire burning, ensuring your horse has a steady supply of fiber to ferment for sustained heat production.
This is why, when the temperature plummets, experienced horse people don’t just dump more grain in the bucket. They throw more hay. That long-stem fiber keeps the internal fire stoked all night long.
The Alfalfa vs. Grass Hay Showdown
So, if all hay creates heat, why do people specifically talk about feeding horses alfalfa in winter? Is it really that different from your standard Timothy or Orchard grass hay?
The answer lies in the composition of the hay itself. It's important to match the hay to your horse's nutritional needs and ensure it fits into the overall horse's diet for optimal health and performance.
Timothy hay is a popular choice for horse owners due to its consistent quality and balanced nutrients, providing moderate protein and energy levels.
Orchard grass hay is a soft, palatable grass hay with moderate protein and energy levels, making it suitable for many horses.
Alfalfa hay is a nutrient-dense forage valued for its higher protein, calorie, and calcium content, making it an excellent option for horses with increased energy needs. It supports weight maintenance and muscle development, though it should be fed thoughtfully to avoid excess intake in easy-keeping horses. (Horses that have no problem putting on weight.)
Mixed hay combines both grass and legume hays (for instance, a combination of Timothy and alfalfa, providing a balanced option that meets the needs of many horses.
When comparing alfalfa and grass hay, it's important to note that different hays provide varying energy levels, which can help you select the best option for your horse's needs during winter.
The Science of Alfalfa
Alfalfa hay is technically a legume hay, not a grass. As a legume hay, alfalfa offers unique benefits, including a richer nutritional profile and suitability for horses needing extra support, such as those with dental issues or higher energy demands:
High Protein: Alfalfa is rich in high protein, supporting muscle development and maintenance.
Higher Digestible Energy: It provides more digestible energy and calories per pound than grass hay, making it a valuable source of extra energy for horses.
Higher Calcium: It brings different minerals to the table, especially high calcium content.
When you feed alfalfa, you are providing extra energy, which is particularly useful for horses with increased caloric needs during winter or periods of higher activity.
When a horse digests protein, the metabolic process creates more heat than digesting simple fiber. Because alfalfa is so high in protein, breaking it down generates a significantly higher “heat increment.”
Imagine you are eating a salad versus a hearty stew. The stew (alfalfa) feels heavier and warms you up from the inside out more intensely than the light salad (grass hay).
So, strictly speaking, alfalfa generates more metabolic heat than grass hay. It also provides more calories per pound, which helps offset the energy your horse burns just trying to stay warm in freezing temps.
That said, if you decide to feed alfalfa hay in the winter, it should not be a set-it-and-forget-it program. Even in colder temperatures, your equine can put on weight. So, always be vigilant of weight gain or loss, and keep in mind their current body condition score.
The Case for Grass Hay
Now, don’t go throwing out all your grass bales just yet!
Grass hay (like Timothy or Orchard) is the bread and butter of the horse world for a reason.
While it might not burn quite as hot as alfalfa, it has a massive advantage: volume. Grass hay is a lower-calorie hay, which means you can feed larger rations compared to alfalfa, especially for easy keepers, horses that tend to gain weight easily, and require careful calorie management. This makes grass hay the preferred choice for these "easy keepers" to prevent obesity and metabolic issues.
Remember the wood stove analogy? Grass hay allows you to keep the fire fed constantly.
When pasture grass goes dormant in winter and is no longer available as a fresh forage source, hay becomes the primary forage for your horse. If you fed a horse free-choice alfalfa (all they can eat), you might end up with a very energetic, very round horse very quickly! Grass hay lets them chew and ferment all day long, keeping a steady, consistent baseline of warmth.
Is Alfalfa the Best Hay for Horses in Winter?
This is where it gets tricky. Just because alfalfa creates more heat doesn’t automatically make it the best hay for horses in winter for every horse. Different horses have different nutritional needs, and what works for one may not be suitable for another, especially when considering factors like age, workload, and health status.
For horses prone to metabolic disorders or laminitis, it's especially important to select low-NSC (non-structural carbohydrate) hay (a forage low in sugars and starch) and test feeding it, as these horses require special diets to prevent complications.
Regularly assessing your horse's body condition and adjusting their hay intake is essential, since horses may need more hay in winter to generate heat through fermentation, but overfeeding can be just as problematic as underfeeding. Monitoring body condition helps ensure your horse stays healthy and comfortable throughout the colder months.
When Alfalfa is the Winner
Alfalfa is a fantastic tool in your winter arsenal if your horse fits a specific profile. Consider adding alfalfa if:
Your horse is a “hard keeper”: Hard keepers are horses that require extra calories and nutrition to maintain body weight and condition, especially in winter or under heavy work. If you have a thoroughbred or a senior horse who struggles to hold weight in the cold, alfalfa is a lifesaver.
You have senior horses: Senior horses often have special dietary needs due to age-related changes, such as difficulty maintaining weight or chewing. They may benefit from the added nutrition and softer texture of alfalfa. Horses with poor dental health may struggle to chew long-stem hay and may benefit from softer hays or hay alternatives.
It is bitterly cold: We’re talking negative temperatures or severe wind chill. That extra heat boost can make a real difference during a polar vortex.
Your horse has high energy needs: If you are still riding heavily, or if you have a pregnant mare or a growing foal, they need those extra calories.
When Grass Hay is the Winner
For the majority of our beloved “backyard buddies,” grass hay is often the safer primary forage. It can be an excellent part of a balanced nutrition plan for most horses, providing necessary fiber and energy without excess calories.
You should stick mainly to grass hay if:
Your horse is an “easy keeper”: If your horse gains weight just looking at food, stick to grass hay so they can keep eating and staying warm without ballooning.
Your horse has metabolic issues: Horses with Cushing’s or Insulin Resistance need to be very careful with sugar and starch. While alfalfa is low in sugar, its high calorie count can still be an issue for weight management.
Your horse is idle: If you aren’t riding much in the winter, they likely don’t need the rocket fuel that is alfalfa.
The "Secret Weapon": The Mix
Here is the secret that veteran horse owners know: you don’t have to choose just one! For most horses, the best hay for horses in winter is actually a blend.
I like to think of it like making a perfect winter soup. You need the broth (grass hay) for volume and hydration, and you add the meat and veggies (alfalfa) for substance. For winter feeding, blending different types of winter hay—such as grass and legume hays—can help provide a more complete nutritional profile to support your horse’s health.
Try this strategy: Feed grass hay as the main course. Give them as much as they need to keep munching happily. Then, use alfalfa as a “top dressing” or a special meal during the coldest parts of the day—usually at night.
Throwing a flake of alfalfa to your horse right before you turn off the barn lights is like tucking them in with a heated blanket. It gives their digestion a high-calorie, high-heat task to work on through the coldest hours of the night.
It’s Not Just What You Feed, But How You Feed
While we are obsessing over the type of hay to feed your horse(s) during the winter months, we often miss the forest for the trees. Feeding hay properly is crucial, as the method you use can impact both your horse’s health and the amount of hay wasted.
An empty stomach is a cold stomach. When planning for winter, it’s important to calculate how much hay your horse will need by considering their weight, daily intake, and potential wastage to ensure you have enough supply.
Hay waste can be significant, especially when feeding round bales or placing hay directly on the ground, where it'll be trampled and defecated on. So, make sure you're putting out enough for them when factoring in the waste factor.
The Importance of "Chew Time"
Horses are designed to graze for 16+ hours a day. In the winter, when the pasture is covered in snow, we have to replicate that.
Use Slow Feeders: These are hay nets with small holes that force the horse to eat slowly. Slow feeders help mimic natural grazing patterns by encouraging horses to eat small amounts over a longer period, supporting steady forage intake. This not only makes the hay last longer but also benefits gut health by promoting continuous chewing and proper digestion, especially in the hindgut. Utilizing nets or feeders also helps reduce waste from mud and snow. (Here is an example of a slow feeder used with round bales.)
Feed More at Night: As mentioned, night is when the temperature drops. I always save my biggest feeding for the evening.
Water: The Forgotten Nutrient
You cannot talk about hay without talking about water. A horse eating dry hay needs a lot of water to keep things moving in the gut. When horses consume high volumes of dry hay in winter, it is essential that they have constant access to fresh water to ensure proper hydration and prevent colic. If they get dehydrated, that fermentation process slows down, and you risk colic.
Warm Water Works Wonders: Horses prefer water that is around 45-65°F. If the water is freezing cold, they won’t drink enough. Investing in a tank heater or carrying warm buckets is one of the best things you can do for their digestion.
Best Practices for Hay Storage
When old man winter rolls in and your pastures go dormant... well, hay becomes everything. (and I mean everything.) That's why I can't stress enough how important it is to store quality hay properly, just as important as picking the right type in the first place.
Here are some lessons that have been learned over the years—some of them through trial and error (mostly error, if I'm being honest):
Keep Hay Dry and Covered: Moisture... man, it's the absolute enemy of good hay. Ideally, you can store it in a well-ventilated barn or, at the very least, under a sturdy tarp to keep rain and snow off it. Wet hay develops mold faster than you'd believe, and it's not just that horses won't eat it—it can actually mess up their digestive health pretty badly.
Elevate Off the Ground: Stack that hay on pallets or some kind of raised platform... trust me on this one. Ground moisture will creep in and ruin everything if you're not careful. This simple step—and it really is simple—helps keep your forage solid and cuts down on spoilage big time.
Allow for Airflow: Good ventilation is absolutely key here. (I can't emphasize this enough.) You've got to prevent condensation and heat buildup, which leads to mold or—and this one scared me when I first heard about it—spontaneous combustion in those tightly packed bales. Arrange your bales with a little breathing room between stacks... it makes all the difference.
Rotate Your Stock: Use the oldest hay first, keep the newer stuff at the back. This whole "first in, first out" thing... It's not just fancy business talk. It actually ensures your horses get the freshest, highest-quality hay you've got available. Every single time.
Check Regularly for Quality: Even when you're doing everything right with storage, you still have to inspect the hay regularly. (I make it part of my routine now.) Look for dust, mold, any kind of off smell... and don't hesitate to pull questionable bales before they make it to your horse's feeder. Better safe than sorry, always.
Following these storage tips will help you preserve the nutrients and energy your horses need to stay warm and healthy throughout those long winter months (and save you money in the long run).
My "Winter Warmth" Checklist for New Owners
If your head is spinning a little, don’t worry! We’ve all been there. Here is a simple checklist to help you navigate your first winter.
Assess Your Horse’s Body Score: Run your hands over their ribs. Can you feel them easily? If yes, they might need the calories from alfalfa. If you have to dig to find a rib, stick to grass hay.
Check the Forecast: Keep an eye on the weather. If a massive storm is coming, that is the time to go buy a few bales of alfalfa to supplement their diet for a few days. Changing weather conditions, such as dropping temperatures and increased wind chill, can increase your horse's hay needs to help maintain body warmth.
Buy Quality Hay: Whether it is grass or alfalfa, make sure it is mold-free and not too dusty. Stick your nose in it! If it smells sweet and grassy, it’s good. If it smells musty, toss it. Always plan to buy extra hay so you have surplus on hand for emergencies or unexpected increases in consumption during winter.
Community Matters: Ask a buddy, your veterinarian, or a local trainer what they feed. Local hay varies by region, and they will know what the “norm” is for your area.
When calculating your winter hay supply, round up your numbers to leave a safety margin and ensure you don’t run short during the season.
A Note on Cost (Because We Know Horses Aren't Cheap!)
Let’s be real—budget is a huge factor. Alfalfa is usually more expensive than grass hay.
If you are trying to balance the budget, remember that feeding horses alfalfa in winter doesn’t have to be an all-or-nothing proposition. You don’t need to feed pure alfalfa to get the benefits. Buying just ten bales of alfalfa to use strictly as a “cold night treat” or supplement can make a huge difference without breaking the bank.
Also, compare the cost per calorie. Sometimes, because alfalfa is so nutrient-dense, you feed less of it, which can actually balance out the cost. However, be careful not to provide excess calories, as overfeeding can lead to weight gain and other health issues, especially if your horse is not in heavy work. But for a novice, sticking to a grass hay base is usually the most economical and safest route.
The Bottom Line
So, back to our original question: Best hay for horses in winter?
The truth is, the "best" hay is the one that keeps your specific horse at a healthy weight and keeps their belly full.
True: Alfalfa does create more internal heat.
True: Alfalfa provides excellent energy for cold weather.
But: Grass hay provides the vital long-term chew time and volume needed for sustained warmth without the risk of obesity for easier keepers.
Don't let the pressure get to you. I know it feels like a huge responsibility to keep these big, beautiful animals comfortable when it’s freezing outside. But nature built them to handle this! Their winter coats are amazing, and their digestive furnaces are powerful.
Trust your gut (and their hindgut!). If your horse is maintaining weight, has a bright eye, and isn't shivering, you are doing a great job.
If you are ever unsure, don't hesitate to ask a vet or an equine nutritionist. In our community, there are no stupid questions—only opportunities to learn and do better for our horses.
Stay warm out there, and happy feeding!