I grew up on a dairy farm and learned early in my life that cow manure is useful. That usefulness may have been born out of necessity, though. After all, the manure from a herd of 50 cows has to go somewhere right? My grandpa showed me cow manure makes a great fertilizer. But we never had horses on our farm so I started wondering if horse manure is useful as a fertilizer too.
Although there is a wide range of weights among horses depending on the breed, an average adult riding horse weighs approximately 900 pounds. A horse that size produces around 8 to 9 tons, or between 16,000 and 18,000 pounds of manure every year. That’s a lot of horse manure. I mean truck loads.
What is done with that manure? One option for disposal is to haul it to a landfill site, but that is not an eco-friendly option and some landfills will not accept horse manure. The best option is to spread the horse manure on land so it decomposes quickly, or to compost it and then use it to improve soil quality.
One problem with using horse manure to fertilize ground is that many people use sawdust or wood chips as bedding in horse stalls. When the stalls are cleaned, the dirty sawdust or wood chips are removed with the horse manure. While the horse manure itself is a good fertilizer, the sawdust and wood chips are not crop friendly. When wood breaks down in the soil a nitrogen deficiency occurs, which stunts the growth of crops. To combat this problem, a nitrogen fertilizer can be added to the soil after horse manure is spread on it; or a nitrogen fertilizer can be added to the horse manure and sawdust or wood shavings mixture before being added to the soil.
A great way to use horse manure is to add it to a compost pile. When adding the manure to a compost pile, any sawdust and wood chips present in the manure are okay. They are a good “brown” component to compost. It takes about six months for the manure, sawdust or wood chips, and any other materials added to the compost pile to completely break down. When the compost process is complete, it becomes what many people call “black gold”.
To make a compost pile with horse manure as one of the components, layer it with green compost items. Many experts suggest alternating layers of brown and green compost items because you need sources of both carbon (brown items) and nitrogen (green items) in your compost pile. Brown items such as horse manure, wood chips, and sawdust are great sources of carbon. A few good sources of nitrogen (the green items) for a compost pile include: green leaves, fresh grass clippings, the scraps from raw fruits and vegetables, and coffee grounds. Yes, coffee grounds are brown, but for the purposes of compost they are considered a green item because they provide the compost pile with nitrogen.
Because the compost pile is a living thing, it needs water and air to thrive. Your compost pile should be turned each week, adding water as needed to keep the compost pile damp. You’ll know the process of breaking down has completed when the compost material is dark and crumbly and fresh smelling. The pile will not be giving off heat when the material is ready to use.
Once the horse manure and other materials have turned into the “black gold”, it’s finally time to put it to good use. While compost isn’t officially considered a fertilizer, it contains nutrients that are great for plants and soil. Some good ways to use your horse manure compost are: as mulch for garden plants and around landscaping; as a soil improvement component for sandy soil; as a soil improvement for clay soil; and as a material to help control erosion.
Now you know that horse manure, that smelly waste product from a beloved animal, is a useful by product that is environmentally friendly. Give it a try, your plants will thank you!