How deep are the crowns? If they are too deep, they often won't bloom and if you mulch your plants where the crown ends up being too deep, that is often the reason they don't bloom. Do not set the crown (i.e., the point where foliage and roots join) more than 1 inch below the surface of the soil. Also, if the clump is too big and is in need of dividing, that can affect bloom.
