Horse manure and scorching

Question ...

I have what seems to be an endless supply of fresh horse manure. This breaks down nicely in my compost heap, but takes around a year or more to become a good, dark-brown humus. I know that horse manure is supposed to be 'fiery' but what harm can be done by surface mulching fallow and veg beds with the fresh stuff?

Answer ...

If placed around growing plants, fresh manures will scorch the plants. Using fresh manure on the fallow beds should be fine, although if it is applied in autumn and winter it is likely that the nutrients it contains will be washed out and lost during periods of rainfall. Manures are most valuable when composted with some form of bedding material, such as straw and hay. Urine is the main source of the plant nutrients contained in manures, particularly nitrogen and potassium, and is soaked up by the bedding. The composting process stabilises these nutrients, which might otherwise be washed out by the rain, and converts them to a form that is more readily taken up by plants.

Fresh horse manure can also contain chemicals used to worm horses. These chemicals are broken down during the composting process.

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