Yerba mansa flowering

[1wheeler1743@att.net]

I purchased a Yerba mansa (Anemopsis californica) from the CNPS sale in SLO about two winters ago. It is planted in a perennially moist soil at the base of a north facing fence with about four to five hours of sun a day. The plant grows vigorously throughout the Spring and Summer but has produced no flowers. When can I expect this plant to flower? Are there conditions it must meet, or an age it must reach, before flowering?

Tom