Spring Forward: Nutritional Strategies for Transitioning Your Horse into the New Season

As winter eases and spring breathes new life into pastures and paddocks, horse owners are often eager to let their horses enjoy the lush green grass and warmer weather. But transitioning your horse from a winter feeding routine to a springtime diet isn’t as simple as throwing open the gates. Horses need a careful, thoughtful shift in nutrition to stay healthy and perform at their best while adjusting to seasonal changes.

The warmer, longer days that come in Spring causes a dramatic change in pasture composition, especially in cooler or temperate climates where C3 type grasses and clovers flourish. The fresh, fast-growing grasses of spring are often high in non-structural carbohydrates including sugars and starches. If not managed properly, this abundance can lead to digestive disturbances, laminitis, and metabolic flare-ups—especially in sensitive horses.

Here’s a comprehensive look at the nutritional adjustments every horse owner should consider when transitioning their horse to spring.

1. Monitor Body Condition: Are You Feeding for the Right Weight?

One of the first steps in preparing for spring is evaluating your horse’s body condition. Winter rugging, long hair and reduced riding often mask changes in body weight, and once the blankets come off, owners may be surprised to see a fuller or leaner horse than expected.

Use a Body Condition Score (BCS) system, typically on a scale of 1 to 9, to objectively assess your horse’s fat cover. Ideally, horses should be maintained at a score of 4 to 6. On the 1 to 9 scale, a BCS of 4 suggests a lean but healthy physique, while a 6 indicates a slightly fleshy horse—not overweight but potentially at risk if left unmanaged.

• If your horse is underweight, gradually increase caloric intake using high-quality forage and, if necessary, grain or concentrates.
• If your horse is overweight, reduce caloric intake by limiting grain and closely monitoring access to pasture.

Remember, even a small adjustment in feed can have significant results over time, and slow, steady changes are safer than dramatic shifts.

2. Adjust Grazing Time: Transitioning Pasture Access Slowly

Horses find the sweet, green grass of spring delicious after a winter with more mature, sparse grass and a significant hay intake. But this grass is rich in starch and sugars—substances that can trigger laminitis and overload a horse’s digestive system if introduced too quickly.

Why does it matter? The microbial population in the equine gut is highly sensitive to the food consumed by the horse. A sudden dietary change, especially from dry hay to lush grass, can disrupt these microbes and lead to colic, hindgut acidosis, and even laminitis.

To avoid these issues, introduce pasture gradually:

• Start with 15–30 minutes of grazing per day and increase the duration by 30 minutes every few days.
• Pay attention to grass growth patterns. The highest sugar content tends to occur on sunny days, especially in the late afternoon and evening.
• Consider morning grazing, when sugar levels are lower, for horses sensitive to sugar intake.

Gradual exposure allows your horse’s microbiome to adapt while giving you time to observe any adverse reactions.

3. Provide Consistent Forage: Don’t Ditch the Hay

It’s tempting to reduce or eliminate hay once the pasture begins to green up. After all, if the field is full of fresh forage, why supplement with dry hay?

But here’s the issue: spring grass is high in water and sugars, and relatively low in fiber compared to hay. Horses need a consistent supply of fibre to maintain gut health and avoid scouring or digestive upset.

To maintain consistency:

• Offer free-choice hay, especially in the early spring weeks when pasture is not yet fully established.
• Choose a mature, lower-sugar hay to balance the rich spring grass.
• Feed hay in slow feeders or nets to encourage natural foraging behaviour and reduce waste.

Even for horses on full pasture turnout, a small daily ration of hay can help ensure they receive adequate fibre and avoid overconsumption of sugary grass.

4. Limit Pasture Access for At-Risk Horses

Some horses are especially vulnerable to the perils of spring grass. Those who are overweight, have EMS or insulin-resistance, or have a history of laminitis require stricter management when transitioning to pasture.

By far the most common cause of pasture-associated laminitis is a spike in blood insulin levels. This is triggered by eating grass, hay or hard feeds high in sugar and starch. During spring and autumn, pastures are naturally high in plant carbohydrates (sugars or starches), putting insulin resistant horses at high risk for laminitis.

The best approach for managing these horses includes:

• Limiting turnout time, providing small amounts of early morning grazing if monitoring is possible. It is especially important to avoid grazing during peak sugar hours – late afternoon and evening.
• Using a grazing muzzle, which can reduce grass intake by up to 80% while still allowing the horse to exercise and interact socially. However, the muzzle must be on whenever the horse has access to pasture. Horses have demonstrated that they can learn when free choice grass is limited to a small part of the day, and are capable of consuming their full daily intake allowance (around 2% of body weight in dry matter), in as little as 4 hours!
• Providing access to a dry lot or laneway system with minimal grass, supplemented with ‘safe’ hay to meet forage needs. ‘Safe’ hay for IR horses and for weight loss is low in sugar and starch levels. Ideally, choose hay which has been analysed and has a combined ESC + Starch value of less than 10%. Although YOU CAN’T PICK A SUITABLE FORAGE JUST BY LOOKING AT IT the safest forages are rapidly growing, mid length leafy grasses of native species or lower sugar introduced grasses. If you do not know the sugar and starch levels of your meadow hay, soak in warm water for 30 minutes or cold water for 60 minutes to remove soluble sugars. Drain and discard soak water before feeding. Remove and discard any uneaten hay at least every 12 hours to avoid mycotoxin contamination.
• Soaking hay can reduce water soluble carbohydrates by 30% but also removes some minerals from the hay which need to be replaced with a quality, concentrated mineral balancer.
• Avoid pastures or hay made from high production grasses such as clover and ryegrass and do not feed cereal (oaten, wheaten) hay or chaff. Limit lucerne hay to no more than 30% of total daily intake. Do not give access to very short pastures (e.g. mowed or over-grazed) or grass carrying filled seed heads.
• Avoid starving the horse by ensuring a dry weight forage intake of 1.5 to 2% of the horse’s bodyweight. Unless the horse is underweight, limit hard feeds to a token amount which carries the all-important vitamins, minerals and omega-3 fatty acids needed to maintain good health.

Don’t wait for problems to arise. If your horse falls into one of these high-risk categories, take proactive steps early in the season. Preventing a laminitis episode is far easier (and more humane) than treating one. Learn more here.

5. Consider Nutritional Supplements Wisely

As with any dietary transition, spring is a good time to revisit your horse’s supplement regimen. The nutrient content of forage—both hay and pasture may vary, and gaps in essential nutrients can arise.

This is particularly true for:

• Minerals such as magnesium, zinc, copper, and selenium, which are almost always deficient in forages. During spring and autumn, rapidly growing, heavily fertilised or stressed grass may become high in potassium and nitrate and low in sodium which can have a dramatic effect on electrolyte balance and metabolism in horses, potentially leading to colic, “grass-affected behaviour,” grass tetany or grass staggers. We recommend the Equine Vet&Min range of balancers – with 6 different blends there’s one to suit every horse!

• Electrolytes, including salt which become even more important as horses begin to sweat more with increasing exercise and temperatures. When pasture macro-mineral levels suddenly change, an increase in dietary salt and magnesium above the ‘normal’ levels is needed to balance the intake.
• Omega-3 fatty acids, which can help reduce inflammation, improve insulin sensitivity, regulate the immune system, support hoof health, and maintain a shiny coat during seasonal shedding. We recommend EVM Omega-3 Plus for an all-in-one solution, Farmalogic Laminitis Fighter to help manage insulin resistant horses and ponies, and Farmalogic Omega Balancer for a better-than-linseeds omega-3 solution.

Avoid the “more is better” mindset. Over-supplementation can lead to imbalances, poor absorption, and wasted money. Work with our team of  university qualified equine nutritionists to tailor supplements to your horse’s needs, especially if your horse has metabolic challenges. Grab an expert diet analysis for just $29.95 and receive a discount voucher for $30 to use on the Farmalogic Online Store!

6. Be Alert to Mycotoxins

Mycotoxins are poisonous compounds produced by various species of microfungi. Warmer, wet weather as well as an abundance of pasture plants and seeds increases the risk of horses ingesting mycotoxin in springtime.

Symptoms of mycotoxin ingestion can be very different between horses but often include some of the following:

⚠️ sudden development of unpredictable, uncharacteristic erratic behaviour

⚠️ photosensitivity (severely ‘sunburnt’ pink skin)

⚠️ greasy heel or mud fever

⚠️ lameness or swollen lower legs

⚠️ girthiness or muscle tightness

⚠️ ill-thriftiness despite good feed

⚠️ head-flicking

⚠️ staggers

⚠️ unusual sweat patterns

⚠️ coarse dull coat.

When mycotoxin load is very high, remove horses from contaminated pasture, feed clean hay/hard feed and feed a quality, broad-spectrum toxin binder that does not bind nutrients or medications. We recommend Farmalogic Grazaid, which contains the broadest-acting blend of toxin binders on the market.

⚠️ DO NOT feed dusty, musty, wet or spoiled hay or hard feed. Learn more about mycotoxins here. If symptoms persist call your vet.

Final Thoughts: Balance, Patience, and Observation

The key to a healthy transition from winter to spring nutrition lies in balance, patience, and vigilance. Monitor your horse’s body condition, make changes gradually, and keep a close eye on behavioural or physical signs that something might be off—such as hoof sensitivity, changes in manure, lethargy or uncharacteristically spooky behaviour.

Nature may be springing into full bloom, but your horse’s digestive system needs time to catch up and horses prone to insulin dysregulation need extra special management. With a strategic approach to nutrition, you can make the season change smooth, safe, and satisfying for your equine companion.

After all, spring should be a time of joy, renewal, and vibrant health—for both you and your horse.

Quick Spring Nutrition Checklist

• ✅ Assess body condition score (BCS)
• ✅ Slowly increase grazing time on fresh pasture
• ✅ Continue feeding hay, even on pasture
• ✅ Limit grass intake for at-risk horses
• ✅ Use grazing muzzles as needed
• ✅ Reevaluate supplements with a qualified nutritionist
• ✅ Watch for signs of digestive upset, mycotoxin symptoms or laminitis.

About the Author
Larissa Bilston is a university qualified equine nutritionist and lifelong horse enthusiast with over three decades of experience in horse care and feed management. Passionate about science-backed horse nutrition and holistic management, she aims to help owners make informed, thoughtful decisions for their equine partners.