I was surprised by the fact that the top photograph is a group I planted last fall and had no idea they were white. They are planted in the side garden under the Clerodendrum tree and the lilacs are planted under the big Cherry tree in the back garden.
They are the sweetest little flowers, about 3" across if even that. The fact that the flower re-curves back is what I like about the look of them. It took a couple of years for the lilac ones to become established before they bloomed, I think it was about three years. Most people would not wait that long for a bulb to bloom. But now this stand of them is over 15 years old........They say there are groups of them in Europe that are hundreds of years old. Martagons are a group of lilies that have been in cultivation since the 1500's. So I would say they are worth growing.
USDA hardiness zone 3 to zone 10