What are the differences between compost and manure, in terms of the effects of amending soil? Most gardeners recommend using compost or make your own compost, but for someone who don’t want to do it by myself, I find compost can be very hard to find in garden centres, while manure (cow/sheep) is widely available. Is manure equivalent to compost? If I can only find manure, what else do I need to add in the soil to increase its quality?
Thank you for contacting the Toronto Master Gardeners. The terms compost and composted manure can be confusing! Compost consists of decomposed plant material while composted manure is decomposed animal feces that have been heated sufficiently through the composting process to remove harmful pathogens. Composted manure contains lots of nitrogen and is also a good source of other nutrients like phosphorous and potassium. Composted plant material also provides important nutrients to the soil but more slowly. It is also the very best thing for amending soil structure. The regular addition of plant compost can help sandy soils hold more water and help to break up the hard clumps of clay soils. Both plant and manure compost have a place in amending garden soil and nourishing plants.
Plant compost is available from nurseries and landscape businesses typically delivered by the cubic yard or metre. It may also be available bagged in smaller quantities. Municipalities also sometimes give away compost from their leaf and yard waste collections. “Garden soils” or triple-mix type soil are mixtures which are not a direct substitute but can be used if plant compost is not available – although the real thing is definitely the best if you can get it.
This website from the University of Minnesota provides additional information about healthy garden soil for your continued reading https://extension.umn.edu/managing-soil-and-nutrients/living-soil-healthy-garden.