Best Exotic Blossom

Rising eight feet above a fibrous, palmlike, olive-green base, this succulent's petals are of an unearthly green-to-aquamarine shade; its stamens are a brilliant poppy-orange. When bumblebees drop by to sip a little nectar, the pollen collects in their rear-leg sacs, turning the sacs the same bright orange color of the stamens: cool. This technicolor glimpse into the wild kingdom all around us is only one highlight of a trip to the arboretum's sere, strangely dazzling cactus garden.