This is Butterfly Weed, Asclepias tuberosa.
The group of milkweed plants is the only food for Monarch butterfly caterpillars.
I love these plants because they are drought tolerant and deer-resistant.
The umbels of flowers are an eye-catching orange.
My favorite feature is the symmetry of the bloom clusters along the stem.
The umbel in the center matures first. Then the adjacent clusters next and so on outwardly.
This symmetry keeps the entire stem balanced.
I find this fascinating.
Form Follows Function.