I have several species of these "Shamrock" plants.
I have the pink buttercup or the Oxalis adenophylla. This one has the green leaves, and the pink flowers.
This one as kids I found out the stalk tastes like sour apples. Now I do not advice eating stuff that one does not know what it is, but us kids ate this!
We had this species growing in our flowerbed where I grew up. I got my bulbs when I bought a aloe Vera plant and someone planted this in with it. I do have mine growing inside the house.
Then there is the purple variety of the Oxalis. I have seen this called the "Charmed Wine". However my plant is two toned and the charmed whine looks like a one tone color?
My plant came to me with a story behind it.
I trade around plants with people and this lady had this one and got it from around about way from Ireland. The story goes that a women saw it in Ireland and just had to bring it back home to America.
This is the story and I notice this one of mine loves to bloom! I feed both species, so this might help....
These flowers are from the purple plant.