Orchard grass is moderate in sugar compared to other cool-season grasses, but it’s not automatically “low sugar” or safe for metabolic horses. Typical orchard grass hay contains roughly 13% to 14% non-structural carbohydrates (NSC), which includes both sugars and starch. That’s above the 10% threshold veterinarians recommend for horses with insulin resistance or laminitis, meaning orchard grass often needs some management to be a good fit for sugar-sensitive animals.
Typical Sugar Levels in Orchard Grass
University of Minnesota research tested orchard grass hay at two growth stages and found NSC levels of 13.8% in vegetative (younger) orchard grass and 14.3% in flowering (more mature) orchard grass. Both exceeded the 12% cutoff sometimes used for horses prone to laminitis, and both were well above the stricter 10% target recommended by the European College of Equine Internal Medicine for horses with metabolic dysfunction.
These numbers place orchard grass in a middle range. It generally runs lower in sugar than ryegrass or timothy cut in late afternoon, but it’s not inherently low enough to feed without caution to a horse that needs a restricted-sugar diet. The only reliable way to know what’s in your specific hay is to have it tested, because growing conditions, harvest timing, and weather create enormous variation from one cutting to another.
What Makes Sugar Levels Swing
Time of Day
Sugar levels in any grass, orchard grass included, follow a predictable daily cycle. Plants use their stored sugars overnight to fuel growth and cell repair, so by dawn the sugar pool is at its lowest point. Once sunlight returns and photosynthesis kicks in, sugars rebuild steadily, peaking in late afternoon or early evening. Studies comparing morning pasture to evening pasture typically find a 2% to 3% increase in NSC by evening. Hay cut in the morning will lock in lower sugar levels than hay cut in the afternoon.
Cold Weather and Frost
Orchard grass is a cool-season grass, and cool-season grasses store energy primarily as fructans, a type of sugar chain held in the stems. During cold weather, these grasses accumulate large amounts of fructans because growth slows down but photosynthesis can still occur on sunny days. The plant keeps producing sugar but isn’t using it to grow, so it piles up. This is why a bright, frosty autumn morning can produce some of the highest-sugar grass of the entire year. The combination of cold nights slowing growth and sunny days driving photosynthesis is the worst-case scenario for sugar accumulation.
Frost itself has a more nuanced effect than most horse owners realize. A frost can initially increase sugar content, but a prolonged hard freeze eventually damages plant cells and can cause sugars to break down or leach out. The net effect depends on the severity and duration of the cold.
Plant Maturity
Most of the sugar and starch in grass is concentrated in the leaves rather than the stems. Younger, leafier growth has a higher proportion of leaf material and therefore packs more sugar per bite. As grass matures and becomes stemmy, overall nutrient density drops, including sugar. However, the trade-off is that mature grass also has lower protein and digestibility, so you can’t simply let orchard grass go to seed and call it a low-sugar solution without considering the rest of the nutritional picture.
Soaking Hay to Lower Sugar
If your orchard grass hay tests above the threshold your horse needs, soaking is the most practical way to pull sugar out. Research on orchard grass hay specifically shows meaningful reductions even with short soaking times:
- 15 minutes in cold water: NSC dropped from 13.8% to 10.3% in vegetative orchard grass, and from 14.3% to 11.6% in flowering orchard grass.
- 30 minutes in warm water: NSC fell to around 9.4% and 8.6% respectively, bringing both below the 10% target.
- 60 minutes in cold water: NSC reached 9.4% and 8.8%.
- 12 hours in cold water: NSC plummeted to 4.8% and 4.0%, though this extreme duration also strips out other nutrients.
Warm water works faster than cold. For most situations, 15 to 30 minutes of soaking is enough to bring moderately high orchard grass hay into an acceptable range. Longer soaks of 7 to 16 hours can reduce water-soluble carbohydrates by 24% to 43%, but they also cause significant dry matter loss (more than double compared to feeding dry hay) and can encourage bacterial growth in warm weather.
How Orchard Grass Compares to Other Hays
Horse owners often choose orchard grass as a “safer” alternative to timothy or cool-season pasture mixes, and in many cases it is a reasonable choice. Its sugar content tends to be lower than that of ryegrass or fescue grown under the same conditions. But it’s not dramatically different from timothy, and individual hay lots vary so widely that a particular bale of timothy could easily test lower than a particular bale of orchard grass. Species matters less than growing conditions, harvest timing, and weather in the weeks before cutting.
For horses with confirmed insulin resistance, the consensus recommendation is hay with NSC below 10%. Orchard grass can meet that target, but it often doesn’t without soaking or careful selection of tested lots. If you’re managing a metabolic horse, testing your hay is far more useful than relying on grass species alone. A basic forage analysis costs $20 to $40 and tells you exactly what you’re working with.
Practical Tips for Managing Sugar Intake
If you’re feeding orchard grass to a horse that needs lower sugar, a few strategies stack in your favor. Buy hay that was cut in the morning rather than the afternoon. Look for hay harvested during warmer growing periods rather than during cool autumn weather when fructan levels spike. Choose slightly more mature cuttings over lush, leafy early cuts. And soak any hay that tests above your target, even for just 15 to 30 minutes.
For grazing, restrict pasture access during late afternoon when sugar peaks. Early morning turnout, before the sun has had time to drive photosynthesis, gives your horse access to the lowest-sugar grass of the day. Be especially cautious during sunny days following cold nights, since that combination maximizes sugar accumulation in cool-season grasses like orchard grass.