I never thought that one day I would see one of my ground-elder "bushes" thriving, spreading, and flowering in full sunlight. All the texts had told me that this plant needed a lot of shade to survive. It turns out that it only needs shade part of the day. This particular bush is right next to a real "wall" of trees and plants to the East. They keep the sun away in the morning and right up until noon. That's enough hours of shade for this ground-elder "bush".