Rain Lily or Atamasco Lily, Zephyranthes atamasca, is a perennial wildflower growing from a bulb. It's showy white trumpet / lily shaped blooms are on display in the spring. It prefers moist soil and grows in full sun to partial sun. Even though Atamasco Lily is evergreen and it can multiply in to a colony, because of it's grass like leaves, it is inconspicuous when it is not blooming.