I found a rare site, over in Paradise Crest when I was doing the post on it the other day. When the agave flowers, it suddenly sends up an enourmous tree like flower. I caught a picture of 2 of them in the same yard.
Agave's are my favorite desert ornamentals. I've had about 20 different varieties over the years at various properties.
I was certainly disheartened the next morning when one of my Agave's that I was growing for the new front yard landscaping just up and died. All the leaves pulled out like an onion blossom at Outback.