With declining monarch butterfly numbers it's no surprise that this year's perennial of the year is Asclepias tuberosa, the butterfly weed. Asclepias means milkweed and indeed, should you pick one, you'll soon see the milky latex sap from the stalk. This North American native plant loves a sunny spot, is drought tolerant AND supports at least twelve different butterfly and moth species. It thrives in well drained soil, preferably sandy to loamy in Zones 4-9. A good companion is Penstemon; they grow in nature together so well that they can even be put in the same planting hole! As pictured, it looks particularly striking when paired with grasses as it might be found in a natural prairie or meadow.
If you want many, it's also easy to grow from seed. In this scenario though don't expect blooms immediately, that's a 2-3 year commitment.