A rare treat to see the flower, and in close-up too: thanks very much, Marilyn!
In mediterranean conditions dasylirions grow quite quickly to a large size, and their flowering stems grow amazingly quickly. We had one in a never-watered cactus and succulent bed at the front of the house, and during one fortnight's stay a flowering stem which had been just visible from the leaf rosette on our arrival had reached bedroom window height by the time we left - too soon to see it actually flower, which we never did. The plant died a couple of years later, after a particularly long dry hot summer (I don't know whether that was the cause).
I think our plant was Dasylirion acrotrichum, but it may have been D. wheeleri like Marilyn's splendid plant. Chief drawback was the row of vicious small spines along each leaf edge, which both species have and which left my arms punctured all over on my rare attempts to tidy off the old dead leaves. Another slighter drawback was that our plant, when it developed a trunk (as it quite quickly did), decided that standing upright was much too hard work in the hot Greek sunshine, so instead it sprawled along the ground - I've seen this happen elsewhere in the Mediterranean.
