Can I compost with just straight horse manure?

Lately we have been asked if composting will be effective if only horse manure is used. Since horse manure is very close to the ideal carbon:nitrogen ratio at 25:1 (the range is between 20:1 and 40:1) it will compost well. However, we have noticed that when people aren't including any stall bedding or paddock footing at all in their compost it becomes very wet and stratified. This discrepancy is most likely due to the wet climate that we experience on the coast. The more moisture in the compost, the higher the nitrogen levels, and the less effectively the manure will compost. Aeration is also important and when no bedding is added to the compost we find that compaction becomes more of a problem.

Generally we recommend combining small amounts of wood-pelleted bedding with each load of manure added to your compost pile. The wood pellets will absorb much of the excess moisture and provide some aeration to your composting system. If you are only adding small loads of horse manure to your compost you may want to consider adding bedding less frequently. Wood-pelleted bedding is inexpensive when used in this manner and is an excellent addition to your compost.

We have also been asked whether gravel from paddock footing is safe to go into the compost system and yes it is. It adds more aeration to the compost and allows for less compaction of the compost pile. The only thing to be mindful of is the impact that gravel may have on your manure spreader. Small particle size should pass through the spreader easily, but this is something to gauge with your own equipment. Good luck and happy composting!