QUESTION: I acquired a plant of Angelica gigas, which I know is monocarpic. If I deadhead the flowers after blooming and do not let it form seed pods, will it come back next year? Is it better to let it go to seed and start new plants? I do not want to lose this plant.ANSWER: I would not gamble and deadhead Angelica gigas. If it dies, you have no seeds to perpetuate it.I am quite fond of this umbellifer - a fancy word for a plant with umbels, an umbel being a relatively flat flower cluster with tiny flowers arising from a single point. A. gigas grows to 3, sometimes 4 feet, with the maroon umbels emerging, seemingly from the maroon stem, in August. Although some books call it a short-lived perennial, I agree monocarpic is more accurate - meaning that it dies after one flowering.I manage to have a few plants of it every year specifically because I do not remove the finished flowers, but let all develop into mature seeds. I let all the seeds fall (or scatter some in a new spot) because I find it is not generous in producing volunteer seedlings. A few germinate the next spring and stay small all year; the next season, most but not all grow to blooming size. Thus, it skips a year of flowering while the young plants establish themselves.After two or three years of letting all the seeds self-sow, you should have enough plants in various stages of growth to assure blooming plants every year instead of every other.

Send your gardening questions to Michael Martin Mills, The Philadelphia Inquirer, Box 8263, Philadelphia, PA 19101, or send e-mail to: Millsm@phillynews.com.