Agave gracilipes may 2005
This plant began to flower in June. It wintered before 2005.

Agave gracilipes begins to flower
Campanula 'Wedding Bells' is to the left, Callirhoe behind

A. palmeri and Yucca schottii in the background 
It was not clear that this is A. gracilipes until the bloom matured. Only then did the  form of the flower stalk, intermediate between the spicate form of  lechuguilla and the racemose form of neomexicana, its putative ancestors, give it away.

The flower is ~ 3 weeks old here