I wouldn't say our soil is poor, but it is not as fertile as the farm where I grew up where Dad used plenty of manure from the animals he raised everything grew very well. I don't use manure but do use alfalfa pellets once a year so my plants are healthy and have plenty of bloom just don't increase as fast as they do on the farm. Meaning I don't have to divide them very often which is good and keeps things more manageable and enjoyable.