The Suisun thistle is perennial .
The Suisun thistle stays in its juvenile stages of life until it is ready to flower and once the rosette reaches its mature phase it can take up to a year or more to develop the leafy stem .
The Suisun thistle is perennial and stays in its juvenile stages of life until it is ready to flower and once the rosette reaches its mature phase it can take up to a year or more to develop the leafy stem .