Answer: Verbascums are usually propagated from seed. Verbascums as a group are usually biennials, although some varieties such as Southern Charm are considered perennials and may bloom the first year from seed if started early enough. If you deadheaded promptly, the seed would not have been mature and thus may not germinate next spring. Since this is a hybrid, your seedlings may probably show some variation, too. To be assured of blooming plants next year you might want to order them again. In some areas verbascum is referred to as common mullein and is considered a weed, but that is a different type from this hybrid. I do not think I would consider this one invasive.
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