The hollyhock can be perennial in mild climates. Many of mine survive for a second season. It also seeds very prolifically in any disturbed ground. The small green donut of immature seeds is considered edible but I don't consider it worth the trouble. The blossoms hoever are delightful in sallades for color and antioxidants. The
seed is so endemic in my soil that it comes up in flats that I am starting other things and I wind up with plants to
sell through our co-op. It can develop a long tap root and used to be planted around out houses and would thrive because it could reach the the contents of the pit below.