I love growing flowers and I trial a bunch of new plants every year. So do well and others... well, not so well.
These are raised beds - filled with an excellent soil-peat blend and well fed (fish emulsion) so the plants in them grow quite well. It is no uncommon for me to get a daylily seedling to bloom in its second year (and to rogue out the poor ones early) with this kind of fertility level.
This is all by way of saying my trial beds are good for growing most perennials and annuals and this is where they now wind up before I put them into the main flower beds.