Horse manure is almost as good as cow manure in the garden. Both contain similar percentages of nitrogen, phosphorous and potassium, the three essential nutrients that plants need. But "dairy manure may be the single most useful soil builder around," says author and gardener Ann Jovejoy.
About this Author
Aileen Clarkson has been an award-winning editor and reporter for more than 20 years, earning three awards from the Society of Professional Journalists. She has worked for several newspapers, including "The Washington Post" and "The Charlotte Observer." Clarkson earned a Bachelor of Arts in journalism from the University of Florida.