Pay Dirt: Using Livestock Manure in the Garden

Do milk cows have the most nutrient-rich manure?

Think of it as “black gold.” When you add aged manure to your garden or field, you’re enriching the soil with nitrogen, phosphorus, potassium and micronutrients. You’re also helping roots penetrate the ground more easily and improving the soil’s ability to hold moisture.

But all manures aren’t the same. Some animal droppings are higher in nitrogen than others. Fresh manure, which has more nitrogen than the aged stuff, can burn plants and usually contains a lot of weed seeds. Worse, it can harbor pathogens like E. coli, which cause serious human illnesses.

That’s why it’s safer to compost, and, to a lesser extent, age or stockpile animal manure before using it. Joyce and Gary Taylor, who own Knobview Farm in Perryville, Ky., use manure from their chickens and cattle to grow certified-organic produce that they sell to schools, restaurants and farmers’ markets.

“Lots of times,” Joyce says, “I’ll stockpile the manure behind the barn for a year, instead of composting it. We don’t water or turn [the stockpiled manure]. By October or November, or after the crops are [harvested], we spread it on top of our fields.” She runs two Massey Ferguson® tractors, a 4-wheel-drive MF4263 and a MF1240, in various gardens on their property. She uses a tiller with the small tractor to plow some of their garden plots, as well as inside their “high tunnels,” or hoop houses, which are greenhouses that extend the growing season. “The 1240 does a perfect job for that.”

Stockpiling and aging, which can take up to a year or longer, let the Taylors avoid the tedious tasks of monitoring and documenting the temperature in a compost heap. But while aging or stockpiling over enough time may kill some weed seeds and pathogens, composting, which generates high temperatures, is the safest way to use animal manure in your garden.

Joyce’s animals don’t provide enough manure for their needs, so she adds fish oil and USDA-certified organic chicken litter to help build up her soil. The Taylors also grow cover crops, such as vetch, wheat and rye, to increase nitrogen in their garden soil.

If your animals don’t provide enough manure for your garden, check the classified ads to find a seller or donor. Livestock owners and county Extension agents may also be able to help you find a source.