What's the difference between Humus, Composted Manure and Top Soil? My local garden center has bags of all three and they are all about the same price. Sometimes I mix the humus and manure and put a shovelful in with my new plantings, and sometimes I mix all 3. Last year, for no particular reason, I used only humus.

Does is matter which one is used as a soil amendment at planting time? I figure any of them are better than nothing, but I'd like to used the best one.

Thanks!

Bart