Manure is the waste product that comes from every living organism. From worm castings to the more familiar cow dung, this waste material contains broken down organic materials that can add a boost to soil. The origins of manure as a fertilizer date back to the dawn of animal use in farming; as the beasts of burden pulled the plow, they’d relieve themselves in the soil they tilled. Farmers noticed the difference it made and today phosphorous and potassium-rich manure has become common practice for organic fertilization.
All manure isn’t the same, and some is not at all appropriate for garden use. “Green” or fresh manure from grazing animals, like pigs, cows, sheep and horses, should not be used directly on the garden, but seasoned for one year to cure it. When it’s too fresh, the amount of natural fertilizer can burn the plants. Green manure may also contain weed seeds, which can grow and make a real mess out of your garden. Manure from birds (like chickens, ducks and geese) or rabbits is okay to use in the garden immediately.Either add manure to compost, spread manure directly on the garden soil or steep manure in water to make “manure tea”—a liquid version of the fertilizer.
Manure from humans and indoor pets (dogs and cats) should not be used in the garden. All of those have the potential to be rich fertilizers, but they also have the potential to carry diseases that can be passed from the soil to plants.
As for the smell… To some extent, the smell of manure is a welcome aroma for those who garden. If you really can’t stand it, cover the spread manure with straw or newspaper. And, of course, if you do use manure as a fertilizer, always remember to wash produce before eating it!