It really
is tough love.
I feel like in my zone, if I
do cut back the flower, it gives me a much stronger root system to deal with the winters (that don't always give us much snow cover for insulation), and honestly a stronger plant for next year. And truly I do get blooms in most cases a little later. The ones that
really hurt (to me) are the ones that only bloom once a year, or if I do fall planting.
I planted 4-1 quart sized mums the 1st year we moved into this place, and cut back all the blooming pretty little flowers... Oh the pain of not having a little bit of fall color in the yard. But the next year, each 1 quart plant had grown its way into a 2 x 2 foot nice, tall plant. It was wonderful!