Do you fertilize your perennials? If you do, you may want to cut back to 1-2 times a year, if that, OR instead, amend your soil with a nice 1/2" top dressing of compost once or twice a year. Why? Some perennials actually become dependent on fertilizers in order to bloom - and that won't do, not on YOUR SHIFT. Oh no! Try compost; it not only brings nutrients to the soil, but it also builds the soil and improves it over time.