Monochromatic Flower

My daughter has an Amaryllis which just started to bloom a few days ago.  Digital photography school had a challenge this last week for a monochromatic (but not black and white) picture.  So, I took these, reduced the yellows and greens and kept the red.  I don't think that this is pure monochromatic, since it has greys in it instead of pinks.  I don't really know how to do that (probably a red filter in PS?) Anyways, I like the first of the three best (I entered this one), but the second has some nice features too, like more texture.