Buttermilk: Substitute an equal amount of soymilk mixed with lemon juice. Allow the mixture to thicken 5 minutes before using. Or substitute an equal amount of vegan sour cream substitute diluted half and half with water. 1 cup buttermilk = 1 cup soymilk with 2 Tblsp lemon juice allowed to sit 5 minutes. 1 cup buttermilk = 1/2 cup vegan sour cream mixed with 1/2 cup water. Sour Cream: Use a vegan sour cream substitute.
Lay down aged cow manure as a top dressing over recently mowed grass. Use bagged commercial aged manure or buy from a reputable bulk dealer. Manure can be used to top dress grass once or twice a year, with the first application in the early spring and the second in the early fall.
Horse manure is easy to compost and takes about four to six weeks to turn from stable waste to garden gold if you do it properly. Composting does take some effort. Constructing a pile 3 by 3 feet and 3 to 4 feet high helps the process to go faster. A purchased or constructed bin helps keep the contents in place.