A good pasture is not just a grassy field surrounded by a fence. It’s a place of beauty, a weed-free meadow where horses graze on nutritional forage. It’s environmentally sound because the lush grass stops rain from running off your property in torrents. A bad pasture, on the other hand, is riddled with weeds and dotted with bald spots where horses have eaten their favorite plants to the ground. Pastures overstocked with horses cause erosion. Without plant matter to help slow the movement of water, each time it rains, sediment, manure, and other debris from your pasture wash into the waterways.

A horse-healthy and eco-friendly pasture is not difficult to create, but it does take some thought and careful planning.

The Right Amount of Land

Susanna Hinds, a grazing land specialist from the National Resources Conservation Service (a division of the USDA) in Indiana, says the first step toward a good pasture is to determine your carrying capacity–how many animals your property can realistically support. For instance, 10 horses left on a few acres will very quickly overwhelm the grass. At best you will have to limit grazing to a couple of hours a day or you’ll essentially have a weedy exercise paddock.

“If you want forage value off of a pasture the rule of thumb is at least two acres per horse, assuming these are standard-sized horses of around 1,000 pounds,” says Hinds. “It will be less land with ponies and more with draft horses.” The minimum carrying capacity of 10 horses is 20 acres, and this is on productive soils with little slope.

Take a Sample

Now it’s time to get to know your land. What kind of soil do you have? What are the nutrient levels? Guessing is an expensive game. Too much fertilizer washes into the waterways and compromises native plant species. Too little means your grass will struggle to grow. The only way to determine the soil nutrient levels and pH is to analyze the soil in each field.

A soil test requires several soil samples from various parts of each field, taken with a probe or spade to a depth of 2 to 3 inches. Kate Norris, district manager of the Prince William Soil & Water Conservation District in Nokesville, Va., says, “The analysis will include levels of phosphorus (P), potassium (K), calcium (Ca), and magnesium (Mg) levels, and the soil pH. You’ll be given fertilizer and pH amendment recommendations based on these results.”

Note that every state is different when it comes to soil sampling. Some extension or soil and water conservation offices will come to your farm and walk you through the process, while others will just provide information. Extension offices are always a great starting place because they will point you in the right direction.

Amendments and Fertilizers

The soil report will tell you the pH of the soil–whether it is acidic or alkaline or somewhere in the middle. Soil pH varies throughout the United States. Western states, for instance, tend to have high pH levels (more basic), while states in the Midwest have low (more acidic) levels. Plants growing in soil with pH levels that are too high or too low will be unable to unlock nutrients, so you must apply amendments first. For high pH the amendment is sulphur or sulphur-containing fertilizer, and for low the amendment is lime. “Knowing how much (lime) to use depends upon your soil test (results),” says Hinds. “You don’t want to apply more than 2 tons (of lime) per acre at any one time.”

It is best to spread an amendment in the fall so it has time to break down and be incorporated into the soil. Spring is okay, but know that its benefits won’t kick in for a while.

Hinds says a soil report will tell you the nutrient levels of your soil in ranges: low, medium, and high. The middle to moderate range is the best for pastures. “It’s best to have a goal of medium range for pasture. This will be most cost-effective and environmentally beneficial,” she says. “Try to fertilize your field in spring, summer, and fall, however, hold off on using fertilizer with nitrogen in the spring. Nitrogen creates leafy top growth and the spring flush will do this naturally. Phosphorus and potassium help with root structure and the overall health of the plant, and so can be spread at any time of the year.”

If you want to use manure as a fertilizer, your extension office can guide you with sampling and recommendations. Norris notes, “Manure is typically fairly low in nutrients, but it really supplies organic matter. The organic material from the compost increases the porosity of clay soil, which helps with infiltration and drainage by allowing some of the water to flow through during rainstorms. The same pore spaces can also help hold some water in the soil, which is helpful during a drought. Increased organic matter can also increase productivity of the soil, and a healthy stand of vegetation reduces soil erosion.”

Hinds says if your soil test results are good, manure might be the only fertilizer you’ll need: “Composted is best, but at least break it down if you’re spreading it fresh–using a manure spreader will break it down in the flinging process. And for pasture use, you can spread the manure whenever you want to.” (Note: Spreading manure in hot, dry weather is best for reducing potential parasite spread.)

Choosing Seed

Bagged pasture mix might seem convenient, but Hinds says not all mixes are good for horses. “Seed mixes often have too many species,” she says. “Horses will always choose their favorite and leave the rest, so try to limit the species to three (reducing menu choices, so to speak, for the sake of a consistent, healthy pasture, and a nutritionally balanced mix of grasses for the horse). Again, the seed mix differs depending upon where you live. Contact your extension specialist for help.”

Horses love orchard grass, and it grows well in most milder temperature regions. Kentucky bluegrass is also good in pastures because it is relatively short and is not going to disappear quickly like the orchard grass. Kentucky bluegrass is not as palatable as orchard grass, but it’s durable and rebounds well from grazing, and horses like it. Orchard grass and Kentucky bluegrass are good choices to grow together because the orchard is a bunch grass (it grows in clumps or tufts, rather than forming a sod or mat) and the Kentucky bluegrass will fill in the spaces around it.

White clover and bird’s-foot trefoil are both legumes and higher-protein plants, and either provides a good example for a third seed type to plant in a mixture. “Legumes are good for horses because of the protein and good for the soil because they fix nitrogen,” says Hinds. “Some clovers (red clover, specifically) can cause slobber(s) and bloat in horses. Bird’s-foot does not.” (Note: Since horses are not ruminants, it is very rare they will develop bloat.)

Fescue is also a common choice because it thrives in most places, is hardy, and is drought-resistant. But the old Kentucky 31 variety–the most common grazing grass–was problematic because an endophyte fungus in the grass caused problems in broodmares (fertility issues, prolonged gestation, oversized foals, foaling problems, thick placentas, and lack of milk). “Endophyte-friendly” (containing an endophyte that is not harmful) fescue replaced Kentucky 31 and has all its benefits, without the limitations.

Sowing Seed

The best way to establish your field when planting is with a seed drill, which will give the best seed-to-soil contact. Your extension specialist or soil and water conservation district personnel can help you locate one to rent.

Before seeding, mow your grass closely to weaken existing vegetation. This gives the new seeds a chance to germinate without encroachment from less desirable grasses. If you have a lot of potentially harmful weeds, you might need to spray with a broad-spectrum herbicide like Roundup (glyphosate) first and kill off all vegetation on the field. The disadvantage of completely starting over is that you can’t have horses on the pasture until the new plants are established, which can take up to a year, says Hinds. “But some herbicides will only kill broadleaf plants so existing grass will be left.”

Avoid Wide-Open Spaces

Aside from the difficulties of catching a horse roaming the back 40, allowing your animals the run of the land is counterproductive. “The biggest problem is that you don’t have any control over where your horse is grazing,” says Hinds. “Horses are picky and will eat their favorite plants first. They will go back to those places over and over again, and soon the plant won’t be able to deal with the pressure and will die. Weeds and other undesirable forages will take over that space. If they have access to a stream, the simple act of walking in it will stir up sediment and potential contaminants (that can damage pasture grasses). Studies have shown this is a larger problem than defecating in the stream.”

Rotational grazing is the key. To rotate, simply divide what you have into paddocks. Hinds says a good rule of thumb is to split pastures into quarters (if your horses don’t get along you might need to have multiple grazing groups). The more you subdivide, the more forage you will have in the pasture and the less hay you’ll have to feed. Even if you can only split one pasture into two paddocks, you will still have some benefit.

“By subdividing your fields you can graze smaller sections more intensely, forcing the horses to graze more uniformly with less waste,” says Norris. “While grazing the herd in one area, the others are allowed to rest and regrow. And grazing one horse per paddock in multiple paddocks simultaneously doesn’t count!”

Depending upon your situation and budget, the dividing fence can be temporary or permanent. A cost-effective choice is horse-friendly electric fencing (see the photo above) with a solar powered unit. Simply pull up the fencing stakes and move them to rotate paddocks.

When grass in the current grazing area gets below 3 inches, it’s time to move the horses to another grazing area or into a “sacrifice area.” It’s important to mow the grazed area after use. Mowing prevents weeds from seeding and cuts less desirable plants to a shorter and more palatable length. How long you should rest the paddock depends upon where you live. This can be for as long as 30 days, but consult your pasture specialist for advice.

Norris says a sacrifice area is an enclosed place with footing, such as wood chips, sand, or even all-weather footing if you want to use the area as a riding arena. A border of lumber around your paddock can help keep the footing from eroding into the surrounding areas. Try to avoid bare soil, which will become muddy during a rainstorm. “You are sacrificing the ground cover in one area for the good of the majority of the grazing system,” says Norris. “If you have more than one turnout group you will need multiple sacrifice areas.”

Take-Home Message

Since many horse people keep their horses where they live, not only will a healthy pasture benefit both horses and the environment, but it will be pleasing to the eye. Just think of it as a lawn with multiple uses