I love 'Husker Red' penstemon as a cut flower as well as a landscaping plant. The arching purple stems above purple foliage are laden with small white flowers that look great in a bouquet.
But I think I went overboard when I bought a flat of 72 plants a couple of years ago. Every one of those plants throws 30 to 40 stems over about two weeks in spring. That's more than 2,000 stems, over two weeks, for a minor filler flower. There's just no way I can sell that many during its short period of bloom. This year, I sold my first bunch on June 2 and my last bunch on June 10. They might have looked good a bit longer, but we got some fierce wind that dried the delicate petals. Since then, I've sold some stems of the dark, almost black, pods that follow the flowers. But I've got way more of those than I could ever use.
Another perennial that falls into the category of "too much of a good thing" is Kniphofia, shown at right. Also known as red hot poker or Tritoma, this weird spiky flower blooms in various shades of yellow and orange. I guess it's an acquired taste, because I like it more than I did when I first grew it. Even so, it's a hard one to use in an arrangement, and the florists I work with want only a few bunches a week. Again, it's good for about two weeks and then it's done for the year here.
Lysimachia clethroides, or gooseneck loosestrife, is another wonderful white flower. But no matter how few you plant, you will at some point have too many. They spread like mint when planted in good soil. They, too, have a short period of bloom in hot climates. They start to bloom in mid June and by the time the heat of July arives, they start to look brown and tired.
Even more invasive is tansy. I have it in a semi-wild area of the flower fields and it just keeps expanding its range. The golden button-like flower clusters are really great in a bouquet, and I am happy to have them. But they come and go pretty quickly.
This is not to say that all perennials are too short-lived to grow in abundance. Some, like delphiniums, keep on blooming for months. Others, such as alliums and liatris, store well in the cooler. When they bloom all at once, we cut them and sell them over several weeks.
My goal is to have just enough of every kind of flower to meet market demand. That kind of streamlined production would reduce weeding and watering to the bare essentials. But if there's one piece of my flower plan where I don't really mind erring, it's in growing an overabundance. Even though I don't sell them, I still get to look at them. So maybe there is no such thing as too much of a gorgeous flower.