Notice how perennials & annuals at garden centers are dwarf? The industry says that consumers (you) want small plants for small gardens. Don’t believe it. Here’s the real reason plants are dwarf: they must fit in these carts for shipping & must have flowers at the time of sale.
And it gets worse. Tall perennials are treated with plant growth regulators to make them dwarf, so if you think you’re buying a dwarf, you’ll be disappointed next year, when it grows out to full size. The hort industry is not helping itself.