Crinium Blossoms in My Chacala Garden

I just added a couple of photos to this post.
My Chacala garden has three of these plants growing in it. They are growing bigger everyday, and are about 4 feet across and four feet high, not counting the blossom stem. Apparently they are Criniums. They seem to blossom either two or three times a year. I am going back to check my notes later. One just finished blooming, and the other just started.
The stalk seems to just shoot up overnight. After a couple of days they look like this.
Then in takes another few days to burst in huge blooms. The blooms are usually between a foot and 18 inches across. Maybe more. This is a totally new plant for me. The first time I saw this plant, I don't remember seeing it anywhere before, and I didn't notice the blossom until it was fully in bloom.
My plant book for this area, Linda Abbott Tripp's "Ornamental Plants and Flowers of Tropical Mexico" was created by a non-gardener. But has been very helpful for me when I am trying to identify a plant. Unfortunately the author doesn't use the Spanish names, which makes it difficult when searching nurseries. Otherwise it's very helpful.
The author says the Crinium is in the Amaryllidaceae family, and is also called Swamp Lily, and Milk and Wine Lady. It seems to like heavy dampish soil and grows from a giant bulb. I have tried various ways to propagate it without success.

I don't want to dig any of the plants up. They are very large. The strapping leaves are often about 5 feet long. I think they are spectacular looking and am glad my landlady planted them here. She thinks she planted one plant about 5 years ago. She doesn't know how the other plants grew up about 10 feet away. Neither do I, but I sure like them.