Coastal bermudagrass hay is a solid forage option for most beef cows, particularly those in maintenance or mid-gestation. When cut at the right stage, it delivers roughly 10 to 12 percent crude protein and 58 to 62 percent total digestible nutrients, which is enough to meet the daily needs of a mature, non-lactating cow. For higher-demand animals like lactating dairy cows or fast-growing calves, Coastal hay alone falls short and needs supplementation.
Nutritional Profile of Coastal Hay
The quality of Coastal hay hinges almost entirely on when it’s cut. At four weeks of regrowth, the hay averages around 13.6 percent crude protein and 57 percent TDN. That’s respectable forage. Let it grow to six weeks, though, and protein drops to about 9 percent while TDN falls to roughly 53 percent. By eight weeks, you’re looking at hay with only 7.5 percent protein and under 48 percent TDN, which won’t sustain most cattle without heavy supplementation.
Coastal hay also runs high in fiber. Typical neutral detergent fiber (NDF) values land around 765 g/kg, which means the hay contains a lot of cell wall material that’s harder for cattle to break down. High NDF limits how much a cow can physically eat in a day because the rumen fills up before the animal gets enough energy. This is one of the main knocks against Coastal hay compared to legume hays like alfalfa, which are lower in fiber and more digestible pound for pound.
Which Cows It Works Best For
Dry beef cows in early to mid-gestation are the sweet spot for Coastal hay. Their nutritional demands are relatively low, and good-quality Coastal hay cut on a four-week schedule can meet those needs without much else added to the diet. Mature bulls in the off-season also do fine on it.
Lactating cows are a different story. Research at Auburn University found that dairy cows fed Coastal bermudagrass hay as their only forage couldn’t maintain normal milk production. Even when paired with moderate levels of grain, performance lagged behind cows eating other forages. The cows did better when Coastal hay was combined with corn silage or pelleted alfalfa plus a generous grain ration, but the takeaway is clear: Coastal hay alone doesn’t provide enough energy or digestibility for cows producing milk at any serious level.
For beef cows nursing calves, the same principle applies in a less extreme way. A lactating beef cow needs more protein and energy than Coastal hay typically delivers, so plan on providing a supplement during that period. Growing heifers and stockered calves also need more nutrient-dense feed than Coastal hay provides on its own.
Why Cutting Schedule Matters So Much
No single factor affects Coastal hay quality more than the age of the grass when it’s cut. Protein declines in a nearly straight line as the plant matures, while fiber increases and digestibility drops. Here’s what that looks like in practice using data from the University of Florida:
- 2-week regrowth: 16% protein, 56% TDN. Very high quality but impractically low yield.
- 4-week regrowth: 13.6% protein, 57% TDN. The best balance of quality and tonnage for most operations.
- 6-week regrowth: 9% protein, 53% TDN. Marginal for lactating or growing cattle without supplements.
- 8-week regrowth: 7.5% protein, 48% TDN. Low quality. Only suitable for dry cows with supplementation.
If you’re buying Coastal hay rather than producing it, ask the seller about the cutting interval. Hay that sat in the field for six to eight weeks before cutting may look fine in the bale but will leave your cows nutritionally short. A forage test from your local extension office costs very little and removes all the guesswork.
Advantages Over Other Warm-Season Grasses
Coastal bermudagrass has stayed popular across the Southeast for decades, and for good reason. It’s a high-yielding grass that can produce 5 to 7 tons of hay per acre with proper fertilization and adequate moisture. It uses water efficiently and thrives on sandy upland soils that wouldn’t support row crops, making it a practical choice on land that might otherwise sit idle.
Compared to common bermudagrass, Coastal produces roughly 40 to 50 percent more hay per acre. It also outperforms Alicia bermudagrass in digestibility by about 10 percent. However, it’s not the top performer in its family. Tifton 44 bermudagrass averages about 7 percent higher digestibility than Coastal and starts growing earlier in spring, extending the grazing and haying season. If you’re in an area cold enough for occasional winter-kill, Tifton 44 also offers better cold tolerance. Coastal is best adapted to Coastal Plain and lower Piedmont regions and can be damaged by hard freezes at higher elevations.
How to Supplement a Coastal Hay Diet
When Coastal hay doesn’t meet your cattle’s protein or energy needs on its own, supplementation fills the gap. Protein is usually the first limiting nutrient, especially with hay cut at six weeks or later. Common protein supplements include cottonseed meal, soybean meal, distillers grains, and corn gluten feed. Protein blocks and liquid supplements are convenient options if you’re feeding cattle in pastures where daily supplementation is impractical.
For energy, corn is the most widely used supplement on beef operations, used by nearly 58 percent of U.S. cow-calf producers who feed energy supplements. Molasses, commercial pellets, and oil seed meals round out the other common choices. During late gestation and early lactation, pairing Coastal hay with an energy-dense supplement helps bridge the gap between what the hay provides and what the cow actually needs.
A practical rule: if your Coastal hay tests below 8 percent crude protein, rumen microbes can’t efficiently digest the fiber, so the cow extracts even less nutrition from the hay than the numbers suggest. Adding a small amount of protein supplement in that situation doesn’t just add protein to the diet. It actually helps the cow get more out of the hay she’s already eating.
Nitrate Risk in Coastal Bermudagrass
Bermudagrass is classified as a low-potential grass for nitrate accumulation, which puts it in a safer category than forages like johnsongrass, fescue, oats, or sorghum-sudan hybrids. That said, no grass is completely immune. Heavy nitrogen fertilization followed by drought stress can push nitrate levels up in any forage. Younger, immature bermudagrass plants are more prone to accumulation than mature stands. If you’ve fertilized heavily and then experienced a prolonged dry spell, testing the hay before feeding is a simple precaution. Under normal growing conditions, nitrate toxicity from Coastal bermudagrass hay is uncommon.