I don't know about the UK, but it is native here in Virginia, US. From what I have read, they like moist soil (good for rain gardens), with good drainage, full sun to part shade, and clay/loam soil. Oh, also they are herbs in the carrot family. Perennial, I didn't see anything about it being a short-lived perennial. Propagation by division or seed. Couldn't find anything to indicate that they are monocarpic. As an herb, I wouldn't expect that. Very pretty. May have to give it a try. Best of luck to you!

I got one if these at a plant sale 6 years and it is still going strong. I bought it to be a larval host plant for butterflies and planted it in an uncultivated strip along my driveway where it has been utterly neglected and subject to intense weed competition. I forget about it most of the time, but can't miss the yellow blooms every spring. I have never noticed it reseeding.

Im in Lexington VA got three from

a frirnds garden about 4 yrs ago. it stopped showing up where it was originally planted but appeared in other areas even out in the front garden, then reappeared where originally planted. My experience is that it appears and disappears at will but is definitely not invasive as the amount has never been intrusive. I love the surprise of yellow blooms here abd there.

According to The Wild Seed Project, "These seeds need a winter or cold period to germinate -a minimum of 60 days below 40°F in moist soil (or sand or vermiculite). Sow outdoors in pots from November through February." The Wild Seed Project is in Maine and I don't know if the UK will have enough cold weather. The Wild Seed Project has instructions, which is to plant in pots and leave them out all winter. I've had good luck following their instructions, but then, I've had a bit of experience growing Maine natives and all their seeds are for Maine natives and from plants grown in Maine.

Alexanders – Golden Alexander (Zizia aurea) Seeds – Wild Seed Project

Autumn and Winter Seed Sowing in Six Easy Steps — Wild Seed Project

We had a very cold winter below zero at times and several snows . We regularly get freezing temps from Dec- early March.

Thank you for these helpful responses. I adore umbellifers and grow quite a lot of them, with varying degrees of success. Angelicas, chaerophyllum and peucedanums can be a bit tricky in my semi-arid climate while molopospermum, selinums, seseli and anthriscus manage much better. Some, such as hog's fennel (peucedanum verticillaire) can take a number of years to reach blooming size...and then promptly die (which is why I wondered if zizia was monocarpic. Obviously, it would be nice if zizia would (gently) reseed without intervention from me but I am also prepared to stratify the seeds in order to provide enough chilling time for successful vernalisation.

Most of the umbellifers I grow are white, or more rarely pink, so I am always on the lookout for a bright spring yellow such as bupleurum, fennel...while being a little wary of over enthusiastic seeders such as smyrnium (perfoliatum and olustatrum).

As companions, these tend to look well with grasses and some taller perennials such as patrinia, gaura and echinaceas...and of course, I always add a few annuals such as ammi and orlaya, as well as allowing parsley, carrots and parsnips to run to seed in their second year. Such a rewarding, yet modest plant family, which forms the backbone of most of my perennial beds and borders. I absolutely could not imagine gardening without that airy froth of delicate laced foliage and floating florets. One of my annual garden highlights is the sight of goldfinches, delicately removing seeds from the heracleums and teasels.

Not to forget the lovely, but elusive swallowtails, which are critically endangered in the UK, existing solely on a single fugitive food plant (peucedanum palustre) in a few square miles of East Anglia and nowhere else in the UK.

I too get very large groups of goldfinches on my seedheads. I have not got the experience you have ! Would have to look up every single plant you name. It’s wonderful that you are so well versed and can grow so many different varieties.