No matter what kind of manure you use, use it as a soil amendment, not a mulch. In other words, don’t put raw manure directly on garden soils. Raw manure generally releases nitrogen compounds and ammonia which can burn plant roots, young plants and interfere with seed germination. In fact, it’s recommended that all animal manure should be aged for at least 6 months. Many gardeners spread fresh manure in the fall and turn it in to the top 6 inches of soil a month before spring planting.
A better treatment is to hot-compost manure before applying it to the garden. Hot composting, where the pile reaches at least 150 degrees F) helps to reduce the probability of passing dangerous pathogens on to people who handle the manure or eat food grown with manure compost. Anywhere from 75 to 90 percent of the plant nutrients fed to animals are excreted in their manure, so it should be no surprise that the stuff is an excellent fertilizer.
