I've grown them indoors, under lights. They may be short-lived, but under lights I've gotten some to persist for at least three years. Many of them will bloom themselves to death; but with frequent trimming, that can be controlled, a bit. Another caution; if you don't harvest the seeds as soon as they are ripe, many of them will scatter and begin growing, almost immediately. In that way, they are extremely prolific, prodigiously blooming, self-pollinating, then producing and scattering large quantities of seed.