i planted a calla lilly of a different color several years in a row. as soon as i planted, the plant matured and died off. then, they refused to come back up for years. thinking the area was dead, i re planted peonies in the area, the peonies struggled but the next year the calla lillies appeared.....they were dormant for many years .....whaa?...why? huh?? they are on the east side of the building getting strong morning sun and shade from noonish on.
Not unheard of! Many times bulbs wake up after long periods of dormancy.