The flower wastes nothing. At the lip of a penstemon bloom, a hairy filament projects like a small brush beneath the floral tube. It is no frill. This plantain-family member turns a bell-shaped corolla into a pollinator corridor: color, curvature, and the so-called bearded tongue direct an arriving bee toward nectar and pollen.That apparent oddity is calculated floral design. In Penstemon, the bea...More